drm: Use const data when creating blob properties

Creating a blob property will always copy the input data so the data
that is passed in can be const.

Signed-off-by: Thierry Reding <treding@nvidia.com>
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 628369c..ce0dd6c 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -978,9 +978,9 @@
 extern void drm_mode_config_cleanup(struct drm_device *dev);
 
 extern int drm_mode_connector_set_path_property(struct drm_connector *connector,
-						char *path);
+						const char *path);
 extern int drm_mode_connector_update_edid_property(struct drm_connector *connector,
-						struct edid *edid);
+						   const struct edid *edid);
 
 static inline bool drm_property_type_is(struct drm_property *property,
 		uint32_t type)