drm: i915 and amdgpu fixes
Merge tag 'drm-intel-fixes-2019-04-04' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

Only one fix for DSC (backoff after drm_modeset_lock deadlock)
and GVT's fixes including vGPU display plane size calculation,
shadow mm pin count, error recovery path for workload create
and one kerneldoc fix.

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190404161116.GA14522@intel.com