Merge remote-tracking branch 'airlied/drm-next' into drm-intel-next-queued

Git got absolutely destroyed with all our cherry-picking from
drm-intel-next-queued to various branches. It ended up inserting
intel_crtc_page_flip 2x even in intel_display.c.

Backmerge to get back to sanity.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>