I have the same issue.
OpenCL was working before upgrading from Linux Mint 20.3 to 21.

Now clinfo reports: Number of platforms 0

No OpenCL in Darktable or LibreOffice.

My inxi system information:

System:
  Host: AsusDesktop Kernel: 5.15.0-52-generic x86_64 bits: 64 compiler: gcc
    v: 11.2.0 parameters: BOOT_IMAGE=/boot/vmlinuz-5.15.0-52-generic
    root=UUID=99495eea-6ba1-4277-913f-75f857438009 ro quiet splash
  Desktop: Cinnamon 5.4.12 tk: GTK 3.24.33 wm: Mutter vt: 7
    dm: LightDM 1.30.0 Distro: Linux Mint 21 Vanessa base: Ubuntu 22.04 jammy
Machine:
  Type: Desktop System: ASUS product: N/A v: N/A serial: <superuser required>
  Mobo: ASUSTeK model: PRIME B550M-K v: Rev X.0x
    serial: <superuser required> BIOS: American Megatrends v: 2803
    date: 04/28/2022
Battery:
  Device-1: hidpp_battery_0 model: Logitech Wireless Keyboard
    serial: 4023-00-00-00-00 charge: 55% (should be ignored) rechargeable: yes
    status: Discharging
  Device-2: hidpp_battery_1 model: Logitech Wireless Mouse
    serial: 4022-00-00-00-00 charge: 55% (should be ignored) rechargeable: yes
    status: Discharging
Memory:
  RAM: total: 15.42 GiB used: 3.17 GiB (20.5%)
  RAM Report:
    permissions: Unable to run dmidecode. Root privileges required.
PCI Slots:
  Permissions: Unable to run dmidecode. Root privileges required.
CPU:
  Info: model: AMD Ryzen 5 5500 bits: 64 type: MT MCP arch: Zen 3
    family: 0x19 (25) model-id: 0x50 (80) stepping: 0 microcode: 0xA50000D
  Topology: cpus: 1x cores: 6 tpc: 2 threads: 12 smt: enabled cache:
    L1: 384 KiB desc: d-6x32 KiB; i-6x32 KiB L2: 3 MiB desc: 6x512 KiB
    L3: 16 MiB desc: 1x16 MiB
  Speed (MHz): avg: 3276 high: 3895 min/max: 400/4267 boost: enabled
    scaling: driver: amd-pstate governor: schedutil cores: 1: 2859 2: 3533
    3: 2856 4: 3202 5: 3444 6: 2858 7: 3690 8: 3328 9: 3397 10: 3399 11: 3895
    12: 2859 bogomips: 86407
  Flags: 3dnowprefetch abm adx aes aperfmperf apic arat avic avx avx2 bmi1
    bmi2 bpext cat_l3 cdp_l3 clflush clflushopt clwb clzero cmov cmp_legacy
    constant_tsc cpb cppc cpuid cqm cqm_llc cqm_mbm_local cqm_mbm_total
    cqm_occup_llc cr8_legacy cx16 cx8 de decodeassists erms extapic
    extd_apicid f16c flushbyasid fma fpu fsgsbase fsrm fxsr fxsr_opt ht
    hw_pstate ibpb ibrs ibs invpcid irperf lahf_lm lbrv lm mba mca mce
    misalignsse mmx mmxext monitor movbe msr mtrr mwaitx nonstop_tsc nopl npt
    nrip_save nx ospke osvw overflow_recov pae pat pausefilter pclmulqdq
    pdpe1gb perfctr_core perfctr_llc perfctr_nb pfthreshold pge pku pni
    popcnt pse pse36 rapl rdpid rdpru rdrand rdseed rdt_a rdtscp rep_good sep
    sha_ni skinit smap smca smep ssbd sse sse2 sse4_1 sse4_2 sse4a ssse3
    stibp succor svm svm_lock syscall tce topoext tsc tsc_scale umip
    v_spec_ctrl v_vmsave_vmload vaes vgif vmcb_clean vme vmmcall vpclmulqdq
    wbnoinvd wdt x2apic xgetbv1 xsave xsavec xsaveerptr xsaveopt xsaves
  Vulnerabilities:
  Type: itlb_multihit status: Not affected
  Type: l1tf status: Not affected
  Type: mds status: Not affected
  Type: meltdown status: Not affected
  Type: mmio_stale_data status: Not affected
  Type: retbleed status: Not affected
  Type: spec_store_bypass
    mitigation: Speculative Store Bypass disabled via prctl and seccomp
  Type: spectre_v1
    mitigation: usercopy/swapgs barriers and __user pointer sanitization
  Type: spectre_v2 mitigation: Retpolines, IBPB: conditional, IBRS_FW,
    STIBP: always-on, RSB filling, PBRSB-eIBRS: Not affected
  Type: srbds status: Not affected
  Type: tsx_async_abort status: Not affected
Graphics:
  Device-1: NVIDIA GF116 [GeForce GTX 550 Ti] vendor: eVga.com.
    driver: nvidia v: 390.154 alternate: nvidiafb,nouveau,nvidia_drm pcie:
    gen: 2 speed: 5 GT/s lanes: 16 bus-ID: 01:00.0 chip-ID: 10de:1244
    class-ID: 0300
  Display: x11 server: X.Org v: 1.21.1.3 driver: X: loaded: nvidia
    unloaded: fbdev,modesetting,nouveau,vesa gpu: nvidia display-ID: :0
    screens: 1
  Screen-1: 0 s-res: 2944x1280 s-dpi: 96 s-size: 779x339mm (30.7x13.3")
    s-diag: 850mm (33.4")
  Monitor-1: DVI-I-2 pos: primary,right res: 1920x1200 hz: 60 dpi: 94
    size: 518x324mm (20.4x12.8") diag: 611mm (24.1")
  Monitor-2: DVI-I-3 pos: primary,left res: 1024x1280 hz: 60 dpi: 96
    size: 270x338mm (10.6x13.3") diag: 433mm (17")
  OpenGL: renderer: GeForce GTX 550 Ti/PCIe/SSE2 v: 4.6.0 NVIDIA 390.154
    direct render: Yes
Audio:
  Device-1: NVIDIA GF116 High Definition Audio vendor: eVga.com.
    driver: snd_hda_intel v: kernel pcie: gen: 2 speed: 5 GT/s lanes: 16
    bus-ID: 01:00.1 chip-ID: 10de:0bee class-ID: 0403
  Device-2: AMD Renoir Radeon High Definition Audio vendor: ASUSTeK
    driver: snd_hda_intel v: kernel pcie: gen: 3 speed: 8 GT/s lanes: 16
    link-max: gen: 4 speed: 16 GT/s bus-ID: 0c:00.1 chip-ID: 1002:1637
    class-ID: 0403
  Device-3: AMD Family 17h HD Audio vendor: ASUSTeK PRIME B450M-A
    driver: snd_hda_intel v: kernel pcie: gen: 3 speed: 8 GT/s lanes: 16
    link-max: gen: 4 speed: 16 GT/s bus-ID: 0c:00.6 chip-ID: 1022:15e3
    class-ID: 0403
  Sound Server-1: ALSA v: k5.15.0-52-generic running: yes
  Sound Server-2: PulseAudio v: 15.99.1 running: yes
  Sound Server-3: PipeWire v: 0.3.59 running: yes
Network:
  Device-1: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet
    vendor: ASUSTeK PRIME B450M-A driver: r8169 v: kernel pcie: gen: 1
    speed: 2.5 GT/s lanes: 1 port: e000 bus-ID: 0a:00.0 chip-ID: 10ec:8168
    class-ID: 0200
  IF: enp10s0 state: down mac: 04:42:1a:22:7b:74
  Device-2: Qualcomm Atheros TP-Link TL-WN821N v3 / TL-WN822N v2 802.11n
    [Atheros AR7010+AR9287]
    type: USB driver: ath9k_htc bus-ID: 5-2:3 chip-ID: 0cf3:7015
    class-ID: ff00 serial: 12345
  IF: wlx90f652e5215d state: up mac: 90:f6:52:e5:21:5d
  IP v4: 192.168.43.127/24 type: dynamic noprefixroute scope: global
    broadcast: 192.168.43.255
  IP v6: fe80::a5f0:927d:b847:18a2/64 type: noprefixroute scope: link
  WAN IP: 83.132.152.98
Bluetooth:
  Message: No bluetooth data found.
Logical:
  Message: No logical block device data found.
RAID:
  Message: No RAID data found.
Drives:
  Local Storage: total: 7.12 TiB used: 1.9 TiB (26.7%)
  SMART Message: Required tool smartctl not installed. Check --recommends
  ID-1: /dev/nvme0n1 maj-min: 259:0 vendor: Innovation IT model: N/A
    size: 476.94 GiB block-size: physical: 512 B logical: 512 B
    speed: 31.6 Gb/s lanes: 4 type: SSD serial: 648622209040705 rev: T0918A0L
    temp: 33.9 C scheme: MBR
  ID-2: /dev/sda maj-min: 8:0 vendor: Western Digital
    model: WD20EARX-00AZ6B0 size: 1.82 TiB block-size: physical: 4096 B
    logical: 512 B speed: 6.0 Gb/s type: HDD rpm: 5400
    serial: WD-WMC070076708 rev: 0A80 scheme: MBR
  ID-3: /dev/sdb maj-min: 8:16 vendor: Western Digital
    model: WD3200KS-00PFB0 size: 298.09 GiB block-size: physical: 512 B
    logical: 512 B speed: 3.0 Gb/s type: N/A serial: WD-WCAPD4541215
    rev: 0M21 scheme: MBR
  ID-4: /dev/sdc maj-min: 8:32 vendor: Seagate model: ST2000DM001-1CH164
    size: 1.82 TiB block-size: physical: 4096 B logical: 512 B speed: 6.0 Gb/s
    type: HDD rpm: 7200 serial: W1E6GGQ0 rev: CC27 scheme: GPT
  ID-5: /dev/sdd maj-min: 8:48 type: USB vendor: Intenso
    model: External USB 3.0 size: 2.73 TiB block-size: physical: 4096 B
    logical: 4096 B type: N/A serial: 201702091007B rev: 1402 scheme: MBR
  Optical-1: /dev/sr0 vendor: TSSTcorp model: CDDVDW SH-S203P rev: SB01
    dev-links: cdrom
  Features: speed: 48 multisession: yes audio: yes dvd: yes
    rw: cd-r,cd-rw,dvd-r,dvd-ram state: running
Partition:
  ID-1: / raw-size: 301.68 GiB size: 295.88 GiB (98.08%)
    used: 33.74 GiB (11.4%) fs: ext4 dev: /dev/nvme0n1p6 maj-min: 259:5
    label: N/A uuid: 99495eea-6ba1-4277-913f-75f857438009
  ID-2: /media/vitor/Backup 2 raw-size: 2.73 TiB size: 2.73 TiB (100.00%)
    used: 1.87 TiB (68.5%) fs: ntfs dev: /dev/sdd1 maj-min: 8:49
    label: Backup 2 uuid: 5ED4644BD464278B
Swap:
  Kernel: swappiness: 60 (default) cache-pressure: 100 (default)
  ID-1: swap-1 type: partition size: 15.26 GiB used: 0 KiB (0.0%)
    priority: -2 dev: /dev/nvme0n1p5 maj-min: 259:4 label: N/A
    uuid: 38dfc32d-5be5-435d-b007-b66aef7286d0
Unmounted:
  ID-1: /dev/nvme0n1p1 maj-min: 259:1 size: 50 MiB fs: ntfs
    label: System Reserved uuid: C27089B27089ADAB
  ID-2: /dev/nvme0n1p2 maj-min: 259:2 size: 159.95 GiB fs: ntfs
    label: Windows uuid: C0D6EE67D6EE5CE2
  ID-3: /dev/nvme0n1p3 maj-min: 259:3 size: 1 KiB fs: <superuser required>
    label: N/A uuid: N/A
  ID-4: /dev/sda1 maj-min: 8:1 size: 1.82 TiB fs: ntfs label: Files 2
    uuid: D268A8C568A8A9A5
  ID-5: /dev/sdb1 maj-min: 8:17 size: 298.09 GiB fs: ntfs label: Files 1
    uuid: 7740F788305A85C6
  ID-6: /dev/sdc1 maj-min: 8:33 size: 128 MiB fs: <superuser required>
    label: N/A uuid: N/A
  ID-7: /dev/sdc2 maj-min: 8:34 size: 1.82 TiB fs: ntfs label: Backup 1
    uuid: EEEAF2E1EAF2A4CD
USB:
  Hub-1: 1-0:1 info: Hi-speed hub with single TT ports: 10 rev: 2.0
    speed: 480 Mb/s chip-ID: 1d6b:0002 class-ID: 0900
  Hub-2: 2-0:1 info: Super-speed hub ports: 4 rev: 3.1 speed: 10 Gb/s
    chip-ID: 1d6b:0003 class-ID: 0900
  Device-1: 2-1:2 info: JMicron / USA JMS578 SATA 6Gb/s bridge
    type: Mass Storage driver: uas interfaces: 1 rev: 3.0 speed: 5 Gb/s
    power: 8mA chip-ID: 152d:578e class-ID: 0806 serial: 201702091007B
  Hub-3: 3-0:1 info: Hi-speed hub with single TT ports: 4 rev: 2.0
    speed: 480 Mb/s chip-ID: 1d6b:0002 class-ID: 0900
  Hub-4: 4-0:1 info: Super-speed hub ports: 2 rev: 3.1 speed: 10 Gb/s
    chip-ID: 1d6b:0003 class-ID: 0900
  Hub-5: 5-0:1 info: Hi-speed hub with single TT ports: 4 rev: 2.0
    speed: 480 Mb/s chip-ID: 1d6b:0002 class-ID: 0900
  Device-1: 5-1:2 info: Logitech Unifying Receiver type: Keyboard,Mouse
    driver: logitech-djreceiver,usbhid interfaces: 2 rev: 2.0 speed: 12 Mb/s
    power: 98mA chip-ID: 046d:c534 class-ID: 0301
  Device-2: 5-2:3 info: Qualcomm Atheros TP-Link TL-WN821N v3 / TL-WN822N
    v2 802.11n [Atheros AR7010+AR9287]
    type: Network driver: ath9k_htc interfaces: 1 rev: 2.0 speed: 480 Mb/s
    power: 500mA chip-ID: 0cf3:7015 class-ID: ff00 serial: 12345
  Hub-6: 6-0:1 info: Super-speed hub ports: 2 rev: 3.1 speed: 10 Gb/s
    chip-ID: 1d6b:0003 class-ID: 0900
Sensors:
  System Temperatures: cpu: N/A mobo: N/A gpu: nvidia temp: 53 C
  Fan Speeds (RPM): N/A gpu: nvidia fan: 30%
Repos:
  Packages: apt: 2694 lib: 1476 flatpak: 0
  No active apt repos in: /etc/apt/sources.list
  Active apt repos in: /etc/apt/sources.list.d/inkscape_dev-stable-jammy.list
    1: deb http://ppa.launchpad.net/inkscape.dev/stable/ubuntu jammy main
  Active apt repos in: /etc/apt/sources.list.d/kdenlive-kdenlive-stable-jammy.list
    1: deb http://ppa.launchpad.net/kdenlive/kdenlive-stable/ubuntu jammy main
  Active apt repos in: /etc/apt/sources.list.d/official-package-repositories.list
    1: deb http://packages.linuxmint.com vanessa main upstream import backport
    2: deb http://archive.ubuntu.com/ubuntu jammy main restricted universe multiverse
    3: deb http://archive.ubuntu.com/ubuntu jammy-updates main restricted universe multiverse
    4: deb http://archive.ubuntu.com/ubuntu jammy-backports main restricted universe multiverse
    5: deb http://security.ubuntu.com/ubuntu/ jammy-security main restricted universe multiverse
  Active apt repos in: /etc/apt/sources.list.d/savoury1-ffmpeg4-jammy.list
    1: deb http://ppa.launchpad.net/savoury1/ffmpeg4/ubuntu jammy main
  Active apt repos in: /etc/apt/sources.list.d/savoury1-vlc3-jammy.list
    1: deb http://ppa.launchpad.net/savoury1/vlc3/ubuntu jammy main
  Active apt repos in: /etc/apt/sources.list.d/stellarium-stellarium-releases-jammy.list
    1: deb http://ppa.launchpad.net/stellarium/stellarium-releases/ubuntu jammy main
  Active apt repos in: /etc/apt/sources.list.d/ubuntuhandbook1-darktable-jammy.list
    1: deb http://ppa.launchpad.net/ubuntuhandbook1/darktable/ubuntu jammy main
  Active apt repos in: /etc/apt/sources.list.d/ubuntuhandbook1-gimp-jammy.list
    1: deb http://ppa.launchpad.net/ubuntuhandbook1/gimp/ubuntu jammy main
Processes:
  CPU top: 5 of 320
  1: cpu: 26.9% command: apprun.wrapped pid: 113026 mem: 122.1 MiB (0.7%)
  2: cpu: 4.6% command: firefox pid: 2115 mem: 739.8 MiB (4.6%)
  3: cpu: 2.6% command: xorg pid: 1170 mem: 121.8 MiB (0.7%)
  4: cpu: 2.1% command: pulseaudio pid: 1330 mem: 32.5 MiB (0.2%)
  5: cpu: 1.9% command: bashtop started by: bash pid: 20131
    mem: 7.54 MiB (0.0%)
  Memory top: 5 of 320
  1: mem: 739.8 MiB (4.6%) command: firefox pid: 2115 cpu: 4.6%
  2: mem: 295.3 MiB (1.8%) command: cinnamon pid: 1714 cpu: 1.4%
  3: mem: 197.7 MiB (1.2%) command: firefox-bin pid: 2629 cpu: 0.2%
  4: mem: 152.4 MiB (0.9%) command: synaptic pid: 66014 cpu: 0.3%
  5: mem: 150.8 MiB (0.9%) command: firefox-bin pid: 95772 cpu: 0.1%
Info:
  Processes: 320 Uptime: 1h 52m wakeups: 22 Init: systemd v: 249 runlevel: 5
  tool: systemctl Compilers: gcc: 11.3.0 alt: 11 Shell: Bash v: 5.1.16
  running-in: gnome-terminal inxi: 3.3.13

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