Pull ceph fixes from Ilya Dryomov:
"Two rbd fixes for 4.12 and 4.2 issues respectively, marked for
stable"
* tag 'ceph-for-4.15-rc8' of git://github.com/ceph/ceph-client:
rbd: set max_segments to USHRT_MAX
rbd: reacquire lock should update lock owner client id