gralloc: Use ION instead of FIMC

Made also changes to match XXUUMK6.

Needs https://gerrit.nameless-rom.org/#/c/12177/ for video playback and possibly https://gerrit.nameless-rom.org/#/c/12178/

Change-Id: Ia7699406c4bec49c6ec9b4d8b92aaf152094a56d