finish_automount() doesn't need vfsmount_lock for removal from expiry list

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/namespace.c

@@ -2064,9 +2064,7 @@ int finish_automount(struct vfsmount *m, struct path *path)
 	/* remove m from any expiration list it may be on */
 	if (!list_empty(&mnt->mnt_expire)) {
 		namespace_lock();
-		br_write_lock(&vfsmount_lock);
 		list_del_init(&mnt->mnt_expire);
-		br_write_unlock(&vfsmount_lock);
 		namespace_unlock();
 	}
 	mntput(m);