This PR contains several improvement and cleanup patches for the
atmel-hlcdc driver to be applied on drm-next (targeting 4.7).

* 'drm-atmel-hlcdc-devel' of https://github.com/bbrezillon/linux-at91:
  drm: atmel-hlcdc: route DMA accesses through AHB interfaces
  drm: atmel-hlcdc: check display mode validity in crtc->mode_fixup()
  drm: atmel-hlcdc: rework the output code to support drm bridges
  drm: atmel-hlcdc: move output mode selection in CRTC implementation
  drm: atmel-hlcdc: support extended timing ranges on sama5d4 and sama5d2
  drm: atmel-hlcdc: remove leftovers from atomic mode setting migration
  drm: atmel-hlcdc: fix connector and encoder types
  drm: atmel-hlcdc: support asynchronous atomic commit operations
  drm: atmel-hlcdc: add a ->cleanup_fb() operation