drm/udl: fix error-path when damage-req fails

We need to call dma_buf_end_cpu_access() in case a damage-request.
Unlikely, but might happen during device unplug.
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>

drivers/gpu/drm/udl/udl_fb.c

@@ -421,7 +421,7 @@ static int udl_user_framebuffer_dirty(struct drm_framebuffer *fb,
 				  clips[i].x2 - clips[i].x1,
 				  clips[i].y2 - clips[i].y1);
 		if (ret)
-			goto unlock;
+			break;
 	}
 
 	if (ufb->obj->base.import_attach) {