Currently, we run the logrotate scripts as ceph/ceph but that way we
cannot rotate the scripts created by qemu (they are root/ceph and 644).
The original su line was introduced in commit 73d7bed because logrotate
complained that the directory was writable by a non-root group and it
needed a su line to supress that error. This way, we keep the group
settings and we can access and rotate the qemu logs as well.
Signed-off-by: Boris Ranto <firstname.lastname@example.org>