R-Car DU changes for v5.3:

- R8A774A1 SoC support
- LVDS dual-link mode support
- Support for additional formats
- Misc fixes
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190608134652.GE4786@pendragon.ideasonboard.com