drm: add convenience function to create an enum property

Creating an enum property is a common pattern, so create
a convenience function for this and use it where appropriate.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 8d593ad..3b93cdc 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -807,6 +807,10 @@
 #define obj_to_blob(x) container_of(x, struct drm_property_blob, base)
 #define obj_to_plane(x) container_of(x, struct drm_plane, base)
 
+struct drm_prop_enum_list {
+	int type;
+	char *name;
+};
 
 extern void drm_crtc_init(struct drm_device *dev,
 			  struct drm_crtc *crtc,
@@ -904,6 +908,10 @@
 				      struct drm_property *property, uint64_t init_val);
 extern struct drm_property *drm_property_create(struct drm_device *dev, int flags,
 						const char *name, int num_values);
+extern struct drm_property *drm_property_create_enum(struct drm_device *dev, int flags,
+					 const char *name,
+					 const struct drm_prop_enum_list *props,
+					 int num_values);
 extern void drm_property_destroy(struct drm_device *dev, struct drm_property *property);
 extern int drm_property_add_enum(struct drm_property *property, int index,
 				 uint64_t value, const char *name);