drm-misc-fixes before holidays:
- fixup for the lease fixup (Keith)
- fb leak in the ww mutex fallback code (Maarten)
- sun4i fixes (Maxime, Hans)
* tag 'drm-misc-fixes-2017-12-21' of git://anongit.freedesktop.org/drm/drm-misc:
drm: move lease init after validation in drm_lease_create
drm/plane: Make framebuffer refcounting the responsibility of setplane_internal callers
drm/sun4i: hdmi: Move the mode_valid callback to the encoder
drm/sun4i: Fix error path handling
drm/sun4i: validate modes for HDMI