drm: Pass struct drm_file * to __drm_mode_object_find [v2]

This will allow __drm_mode_object_file to be extended to perform
access control checks based on the file in use.

v2: Also fix up vboxvideo driver in staging

[airlied: merging early as this is an API change]

Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 01c34bc..c49fbc4 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -3206,7 +3206,7 @@ struct drm_encoder *
 drm_atomic_helper_best_encoder(struct drm_connector *connector)
 {
 	WARN_ON(connector->encoder_ids[1]);
-	return drm_encoder_find(connector->dev, connector->encoder_ids[0]);
+	return drm_encoder_find(connector->dev, NULL, connector->encoder_ids[0]);
 }
 EXPORT_SYMBOL(drm_atomic_helper_best_encoder);