drm: Don't leak path blob property when updating

Previously, when updating the path blob property, we would leak the
existing one. Make this symmetrical with the tile and EDID blob
pointers.
Signed-off-by: NDaniel Stone <daniels@collabora.com>
Cc: Dave Airlie <airlied@redhat.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/drm_crtc.c

@@ -4304,6 +4304,9 @@ int drm_mode_connector_set_path_property(struct drm_connector *connector,
 	size_t size = strlen(path) + 1;
 	int ret;
 
+	if (connector->path_blob_ptr)
+		drm_property_destroy_blob(dev, connector->path_blob_ptr);
+
 	connector->path_blob_ptr = drm_property_create_blob(connector->dev,
 							    size, path);
 	if (!connector->path_blob_ptr)