drm: drm_auth.c: Adjust end of block comment

Add a new line with */ on the last line of a block comment to follow the
Linux kernel coding conventions.
Problem found by checkpatch.
Signed-off-by: Beatriz Martins de Carvalho <martinsdecarvalhobeatriz@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/cd1e8f6637b914825ee4b9643a4e9d9eba49f276.1618756333.git.martinsdecarvalhobeatriz@gmail.com

drivers/gpu/drm/drm_auth.c

@@ -300,7 +300,8 @@ int drm_master_open(struct drm_file *file_priv)
 	int ret = 0;
 
 	/* if there is no current master make this fd it, but do not create
-	 * any master object for render clients */
+	 * any master object for render clients
+	 */
 	mutex_lock(&dev->master_mutex);
 	if (!dev->master)
 		ret = drm_new_set_master(dev, file_priv);