drm: rcar-du: Fix dot clock routing configuration

Dot clock routing is setup through different registers depending on the
DU generation. The code has been designed for Gen2 and hasn't been
updated since. This works thanks to good reset default value, but isn't
very safe. Fix it.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
1 file changed