Merge tag 'imx-drm-fixes-2017-11-30' of git://git.pengutronix.de/git/pza/linux into drm-fixes

drm/imx: fix commit_tail for new drm_atomic_helper_setup_commit

Since commit 080de2e5 ("drm/atomic: Check for busy planes/connectors before
setting the commit"), drm_atomic_helper_setup_commit expects that blocking
commits have completed flipping before the commit_tail returns. Add the missing
wait_for_flip_done to commit_tail to ensure this.

* tag 'imx-drm-fixes-2017-11-30' of git://git.pengutronix.de/git/pza/linux:
  drm/imx: always call wait_for_flip_done in commit_tail