rbd: initialize rbd_dev->header_oloc early

No reason to delay it until image_id is known.  This will be required
by some rbd_obj_method_sync() callers, after rbd_obj_method_sync() is
changed to take oloc.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jason Dillaman <dillaman@redhat.com>

drivers/block/rbd.c

@@ -4863,7 +4863,7 @@ static struct rbd_device *__rbd_dev_create(struct rbd_client *rbdc,
 	init_rwsem(&rbd_dev->header_rwsem);
 
 	ceph_oid_init(&rbd_dev->header_oid);
-	ceph_oloc_init(&rbd_dev->header_oloc);
+	rbd_dev->header_oloc.pool = spec->pool_id;
 
 	mutex_init(&rbd_dev->watch_mutex);
 	rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED;
@@ -6062,8 +6062,6 @@ static int rbd_dev_header_name(struct rbd_device *rbd_dev)
 	/* Record the header object name for this rbd image. */
 
 	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
-
-	rbd_dev->header_oloc.pool = rbd_dev->layout.pool_id;
 	if (rbd_dev->image_format == 1)
 		ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s",
 				       spec->image_name, RBD_SUFFIX);