i915: Backport watermark fixes for gen9+

[Timo Aaltonen]

[Impact]
5.0 fixes screen flicker issues with new panel models and on hybrid machines, and Intel has prepared a backport for 4.15 which we can use. It consists of 50+ cherry-picked commits plus a handful of build fixes:

git://github.com/vsyrjala/linux.git skl_wm_backport_4.15

[Test case]
Various display configurations with an external monitor connected need to be tested, preferably on a wider set of hardware

[Regression potential]
The backport was done by Intel, and tested with intel-gpu-tools to do the right thing, but there's always a chance of regressing something.

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux-oem - 4.15.0-1035.40

---------------
linux-oem (4.15.0-1035.40) bionic; urgency=medium

  * linux-oem: 4.15.0-1035.40 -proposed tracker (LP: #1819692)

  * [amdgpu] screen corruption when using touchpad (LP: #1818617)
    - drm/amdgpu/gmc: steal the appropriate amount of vram for fw hand-over (v3)
    - drm/amdgpu: Free VGA stolen memory as soon as possible.

  * r8169 doesn't get woken up by ethernet cable plugging, no PME generated
    (LP: #1817676)
    - Revert "PCI/PME: Implement runtime PM callbacks"
    - PCI: pciehp: Disable Data Link Layer State Changed event on suspend

  * Fix I219 doesn't get woken up after plugging ethernet cable (LP: #1817058)
    - e1000e: Disable runtime PM on CNP+

  * i915: Backport watermark fixes for gen9+ (LP: #1817848)
    - drm/i915: Backport gen9+ watermark fixes from 5.0

  * Packaging resync (LP: #1786013)
    - [Packaging] update helper scripts

  [ Ubuntu: 4.15.0-47.50 ]

  * linux: 4.15.0-47.50 -proposed tracker (LP: #1819716)
  * Packaging resync (LP: #1786013)
    - [Packaging] resync getabis
    - [Packaging] update helper scripts
    - [Packaging] resync retpoline extraction
  * C++ demangling support missing from perf (LP: #1396654)
    - [Packaging] fix a mistype
  * arm-smmu-v3 arm-smmu-v3.3.auto: CMD_SYNC timeout (LP: #1818162)
    - iommu/arm-smmu-v3: Fix unexpected CMD_SYNC timeout
  * Crash in nvme_irq_check() when using threaded interrupts (LP: #1818747)
    - nvme-pci: fix out of bounds access in nvme_cqe_pending
  * CVE-2019-9213
    - mm: enforce min addr even if capable() in expand_downwards()
  * CVE-2019-3460
    - Bluetooth: Check L2CAP option sizes returned from l2cap_get_conf_opt
  * amdgpu with mst WARNING on blanking (LP: #1814308)
    - drm/amd/display: Don't use dc_link in link_encoder
    - drm/amd/display: Move wait for hpd ready out from edp power control.
    - drm/amd/display: eDP sequence BL off first then DP blank.
    - drm/amd/display: Fix unused variable compilation error
    - drm/amd/display: Fix warning about misaligned code
    - drm/amd/display: Fix MST dp_blank REG_WAIT timeout
  * tun/tap: unable to manage carrier state from userland (LP: #1806392)
    - tun: implement carrier change
  * CVE-2019-8980
    - exec: Fix mem leak in kernel_read_file
  * raw_skew in timer from the ubuntu_kernel_selftests failed on Bionic
    (LP: #1811194)
    - selftest: timers: Tweak raw_skew to SKIP when ADJ_OFFSET/other clock
      adjustments are in progress
  * [Packaging] Allow overlay of config annotations (LP: #1752072)
    - [Packaging] config-check: Add an include directive
  * CVE-2019-7308
    - bpf: move {prev_,}insn_idx into verifier env
    - bpf: move tmp variable into ax register in interpreter
    - bpf: enable access to ax register also from verifier rewrite
    - bpf: restrict map value pointer arithmetic for unprivileged
    - bpf: restrict stack pointer arithmetic for unprivileged
    - bpf: restrict unknown scalars of mixed signed bounds for unprivileged
    - bpf: fix check_map_access smin_value test when pointer contains offset
    - bpf: prevent out of bounds speculation on pointer arithmetic
    - bpf: fix san...