Merge tag 'ceph-for-5.6-rc2' of https://github.com/ceph/ceph-client

Pull ceph fixes from Ilya Dryomov:

 - make O_DIRECT | O_APPEND combination work better

 - redo the server path canonicalization patch that went into -rc1

 - fix the 'noacl' mount option that got broken by the conversion to the
   new mount API in 5.5

* tag 'ceph-for-5.6-rc2' of https://github.com/ceph/ceph-client:
  ceph: noacl mount option is effectively ignored
  ceph: canonicalize server path in place
  ceph: do not execute direct write in parallel if O_APPEND is specified