When there is no auth cap, check_max_size() can't do anything and may
cause an infinite loop inside ceph_get_caps().
Signed-off-by: N"Yan, Zheng" <zyan@redhat.com>
Reviewed-by: NJeff Layton <jlayton@kernel.org>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>