Merge tag 'drm-sii902x' of github.com:bbrezillon/linux-at91 into drm-next

Add basic support for the sii902x RGB -> HDMI bridge.

* tag 'drm-sii902x' of github.com:bbrezillon/linux-at91:
  drm/bridge: Add sii902x DT bindings doc
  drm/bridge: Add sii902x driver