drm/atomic: Use the new helpers in drm_atomic_helper_disable_all()

for_each_obj_in_state will be removed, so don't use it here.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: David Airlie <airlied@linux.ie>
Link: http://patchwork.freedesktop.org/patch/msgid/20170712081344.25495-4-maarten.lankhorst@linux.intel.comReviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/drm_atomic_helper.c

@@ -2715,13 +2715,13 @@ int drm_atomic_helper_disable_all(struct drm_device *dev,
 			goto free;
 	}
 
-	for_each_connector_in_state(state, conn, conn_state, i) {
+	for_each_new_connector_in_state(state, conn, conn_state, i) {
 		ret = drm_atomic_set_crtc_for_connector(conn_state, NULL);
 		if (ret < 0)
 			goto free;
 	}
 
-	for_each_plane_in_state(state, plane, plane_state, i) {
+	for_each_new_plane_in_state(state, plane, plane_state, i) {
 		ret = drm_atomic_set_crtc_for_plane(plane_state, NULL);
 		if (ret < 0)
 			goto free;