Fix qemu loading of ceph.conf (permission error)

ceph.conf is loaded by qemu, not libvirt.
Since qemu runs as the nova user, ceph.conf owned by root
causes a permission error. The logs in
/var/log/libvirt/qemu/instance-*.log reveal the error.

This change fixes the issue by changing the ownership of ceph.conf
in nova-libvirt to the nova user.

Adapted for Stein and below by amending paths (no cells).

Closes-Bug: #1861513
Change-Id: I1881f51a6c8508f0f186a5623443343dc1df41d4
Signed-off-by: Ning Yao <yaoning@unitedstack.com>
(cherry picked from commit 91910d2a45)
(cherry picked from commit e2c600d9a1)

ansible/roles/nova/templates/nova-libvirt.json.j2

@@ -22,7 +22,7 @@
         {
             "source": "{{ container_config_directory }}/ceph.conf",
             "dest": "/etc/ceph/ceph.conf",
-            "owner": "root",
+            "owner": "nova",
             "perm": "0600"
         }{% endif %}
     ]

releasenotes/notes/bug-1861513-8e09a6fb42dfc99c.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    Fix qemu loading of ceph.conf (permission error).
+    `LP#1861513 <https://launchpad.net/bugs/1861513>`