drm/ttm: set both resv and base.resv pointers

Initialize both ttm_buffer_object->resv and ttm_buffer_object->base.resv
pointers.  This allows to move users from the former to the latter.  When
all users are moved we can drop ttm_buffer_object->resv.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20190805140119.7337-10-kraxel@redhat.com

drivers/gpu/drm/ttm/ttm_bo.c

@@ -1333,9 +1333,11 @@ int ttm_bo_init_reserved(struct ttm_bo_device *bdev,
 	bo->sg = sg;
 	if (resv) {
 		bo->resv = resv;
+		bo->base.resv = resv;
 		reservation_object_assert_held(bo->resv);
 	} else {
 		bo->resv = &bo->base._resv;
+		bo->base.resv = &bo->base._resv;
 	}
 	if (!ttm_bo_uses_embedded_gem_object(bo)) {
 		/*