Merge branch 'primary-plane' of git://people.freedesktop.org/~robclark/linux into drm-next

Here's the latest iteration of the universal planes work, which I believe is
finally ready for merging.  Aside from the minor driver patches to use the
new drm_for_each_legacy_plane() macro for plane loops, these should all have
an r-b from Rob Clark now.

Actual userspace-visibility is currently hidden behind a
drm.universal_planes module parameter so that we can do some experimental
testing of this before flipping it on universally.

* 'primary-plane' of git://people.freedesktop.org/~robclark/linux:
  drm/doc: Update plane documentation and add plane helper library
  drm: Allow userspace to ask for universal plane list (v2)
  drm: Remove unused drm_crtc->fb
  drm: Replace crtc fb with primary plane fb (v3)
  drm/msm: Switch to universal plane API's
  drm: Add drm_crtc_init_with_planes() (v2)
  drm: Add plane type property (v2)
  drm: Add drm_universal_plane_init()
  drm: Add primary plane helpers (v3)
  drm: Make drm_crtc_check_viewport non-static
  drm/shmobile: Restrict plane loops to only operate on legacy planes
  drm/i915: Restrict plane loops to only operate on overlay planes (v2)
  drm/exynos: Restrict plane loops to only operate on overlay planes (v2)
  drm: Add support for multiple plane types (v2)