linux-wandboard

drm/rcar-du: Support per-CRTC clock and IRQ

Some of the DU revisions use one clock and IRQ per CRTC instead of one
clock and IRQ per device. Retrieve the correct clock and register the
correct IRQ for each CRTC.

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