drm: omapdrm: Store the rotation property in dev->mode_config

Rotation is a standard property, store it in
dev->mode_config.rotation_property. While at it, extract the properties
initialization code to a separate function instead of running it for
every plane.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
diff --git a/drivers/gpu/drm/omapdrm/omap_crtc.c b/drivers/gpu/drm/omapdrm/omap_crtc.c
index f456544..7a64765 100644
--- a/drivers/gpu/drm/omapdrm/omap_crtc.c
+++ b/drivers/gpu/drm/omapdrm/omap_crtc.c
@@ -646,9 +646,7 @@
 static int omap_crtc_set_property(struct drm_crtc *crtc,
 		struct drm_property *property, uint64_t val)
 {
-	struct omap_drm_private *priv = crtc->dev->dev_private;
-
-	if (property == priv->rotation_prop) {
+	if (property == crtc->dev->mode_config.rotation_property) {
 		crtc->invert_dimensions =
 				!!(val & ((1LL << DRM_ROTATE_90) | (1LL << DRM_ROTATE_270)));
 	}