feature: enable admin socket and log file for librbd client

we can add below two lines to ceph.conf to enable this

log file = /var/log/ceph/$name.$pid.log
admin socket = /var/run/ceph/$name.$pid.asok

glance charm patch - https://review.openstack.org/#/c/594082

Charm-helpers patch - https://github.com/juju/charm-helpers/pull/204

For the logfile I proposed a new charm-helpers commit here to enable 'log to syslog' and 'err to stderr' (instead of 'log to file') in ceph.conf to solve the logging issue. Full description at the link.
https://github.com/juju/charm-helpers/pull/608

For the admin socket, it's more complicated, so I will do it separately. Currently /run/ceph is managed by systemd-tmpfiles /usr/lib/tmpfiles.d/ceph.conf and is creates as '0770' ceph:ceph which libvirt/qemu process cannot write to. I think probably this should switch to a world writable tmpdir like /var/log/ceph but am evaluating that change. We could potentially write to an alternative location but then the 'ceph' command wont find it automatically and we need to specify th epath manually. After making that change whatever it is there is also code in the various charms around /var/run/ceph and /run/ceph including charm code that does a chgrp to kvm (that doesn't survive a reboot) that needs cleaning up from old bugs like https://bugs.launchpad.net/charm-cinder-ceph/+bug/1779676. Also on focal /run/ceph exists in apparmor but on bionic it doesn't (see: bug #1779674) and also the charm versions of the apparmor profiles that override the packages versions might need a sync.

Also once approved sync to the charms is needed.

Change abandoned by "Billy Olsen <email address hidden>" on branch: master
Review: https://review.opendev.org/c/openstack/charm-nova-compute/+/594082
Reason: Patch has not been updated to address feedback in > 180 days.