misc pull req all over. Biggest thing is the
drm_connector_(un)register_all cleanup from Alexey for drivers without the
load/unload midlayer hooks. I.e. all the new ones, and a bunch of the
pending new atomic drivers depend upon this. Or at least I asked them to
rebase ;-)

* tag 'topic/drm-misc-2016-04-21' of git://anongit.freedesktop.org/drm-intel:
  drm: Make drm.debug parameter description more helpful
  drm: Remove warning from drm_connector_unregister_all()
  drm: probe_helper: Hide ugly ifdef
  drm: rcar-du: Use generic drm_connector_register_all() helper
  drm: atmel_hldc: Use generic drm_connector_register_all() helper
  drm: Introduce drm_connector_register_all() helper
  drm: fix lut value extraction function
  drm/atomic-helper: Print an error if vblank wait times out
  drm/dp/mst: Restore primary hub guid on resume
  drm: Release driver references to handle before making it available again
  drm/i915/dp/mst: Add source port info to debugfs output
  drm/dp/mst: Enhance DP MST debugfs output
  drm/edid: Add drm_edid_get_monitor_name()
  include/drm: Reword debug categories comment.
  drm/crtc_helper: Reset empty plane state in drm_helper_crtc_mode_set_base()
  drm/virtio: Drop dummy gamma table support
  drm/bochs: Drop fake gamma support
  drm/core: Fix ordering in drm_mode_config_cleanup.