Pull in the drm vblank rework from Ville and me. drm core parts acked
by Dave Airlie
Conflicts:
drivers/gpu/drm/i915/intel_display.c
Just a bit of fun around the placement of drm_vblank_on. This merge
resolution has been tested in drm-intel-nightly for a while already.
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>