drm/rcar-du: Rework output routing support

Split the output routing specification between SoC-internal data,
specified in the rcar_du_device_info structure, and board data, passed
through platform data.

The DU has 5 possible outputs (DPAD0/1, LVDS0/1, TCON). SoC-internal
output routing data specify which output are valid, which CRTCs can be
connected to the valid outputs, and the type of in-SoC encoder for the
output.

Platform data then specifies external encoders and the output they are
connected to.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
index a340224..680606e 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
@@ -129,14 +129,16 @@
 	rcar_du_crtc_write(rcrtc, DEWR,  mode->hdisplay);
 }
 
-void rcar_du_crtc_route_output(struct drm_crtc *crtc, unsigned int output)
+void rcar_du_crtc_route_output(struct drm_crtc *crtc,
+			       enum rcar_du_output output)
 {
 	struct rcar_du_crtc *rcrtc = to_rcar_crtc(crtc);
+	struct rcar_du_device *rcdu = rcrtc->group->dev;
 
 	/* Store the route from the CRTC output to the DU output. The DU will be
 	 * configured when starting the CRTC.
 	 */
-	rcrtc->outputs |= 1 << output;
+	rcrtc->outputs |= BIT(output);
 }
 
 void rcar_du_crtc_update_planes(struct drm_crtc *crtc)