Installer fails to check for AMD Proprietary Driver

[Maurice Butler]

Tried upgrading with out removing AMD Proprietary video driver for Rx5600XT.
This had been previous installed and forgotten about. The attempt to upgrade left the machine without a graphics interface and first kernel in grub would not boot.
Check for AMD Proprietary drive before installing and abort with warning,

Post upgrade running proprietary AMD driver, 'lspci -v' gives
2f:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Navi 10 [Radeon RX 5600 OEM/5600 XT / 5700/5700 XT] (rev ca) (prog-if 00 [VGA controller])
 Subsystem: Sapphire Technology Limited Navi 10 [Radeon RX 5600 OEM/5600 XT / 5700/5700 XT]
 Flags: bus master, fast devsel, latency 0, IRQ 88
 Memory at e0000000 (64-bit, prefetchable) [size=256M]
 Memory at f0000000 (64-bit, prefetchable) [size=2M]
 I/O ports at f000 [size=256]
 Memory at fcb00000 (32-bit, non-prefetchable) [size=512K]
 Expansion ROM at 000c0000 [disabled] [size=128K]
 Capabilities: <access denied>
 Kernel driver in use: amdgpu
 Kernel modules: amdgpu

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: ubuntu-release-upgrader-core 1:20.04.36
ProcVersionSignature: Ubuntu 5.4.0-84.94-generic 5.4.133
Uname: Linux 5.4.0-84-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.18
Architecture: amd64
CasperMD5CheckResult: skip
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Mon Sep 13 20:25:20 2021
InstallationDate: Installed on 2020-05-21 (479 days ago)
InstallationMedia: Ubuntu 18.04.4 LTS "Bionic Beaver" - Release amd64 (20200203.1)
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=en_NZ:en
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_NZ.UTF-8
 SHELL=/bin/bash
SourcePackage: ubuntu-release-upgrader
Symptom: dist-upgrade
UpgradeStatus: Upgraded to focal on 2021-09-08 (4 days ago)
VarLogDistupgradeTermlog: