Comment 1 for bug 1740222

Reviewed: https://review.openstack.org/530181
Committed: https://git.openstack.org/cgit/openstack/kolla-ansible/commit/?id=a3a0e920e61420e0922bdaa69b8551e51925a6ce
Submitter: Zuul
Branch: master

commit a3a0e920e61420e0922bdaa69b8551e51925a6ce
Author: caoyuan <cao.yuan@99cloud.net>
Date: Wed Dec 27 15:00:26 2017 +0800

    Fix the cinder backup action failed when use external ceph

    when cinder use external ceph, and edit the cinder-backup.conf follow
    the external-ceph-guide.rst, cinder will backup failed because the
    backup_ceph_user is not cinder-backup, the patch to fix it.

    Change-Id: Ie7213c1280b2b8fc0a4648d09d9ba132427952aa
    Closes-Bug: #1740222