Merge tag 'ceph-for-6.8-rc8' of https://github.com/ceph/ceph-client

Pull ceph fix from Ilya Dryomov:
 "A follow-up for sparse read fixes that went into -rc4 -- msgr2 case
  was missed and is corrected here"

* tag 'ceph-for-6.8-rc8' of https://github.com/ceph/ceph-client:
  libceph: init the cursor when preparing sparse read in msgr2