Backmerge drm-next to get at all the good stuff in drm-misc. We need
that because:

- drm_connector_list_iter conversion for i915 needs the core patches.
- Maarten's patches to use the new atomic state iterators also need
  the core patches.
- We need the new link status property to complete the DP retraining
  work, merging through 2 branches wasn't a good idea and we had to
  partially backtrack.
- Chris needs reservation_object_trylock and we want to roll out
  kref_read everywhere.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>