ceph: move osd data to /var/lib/ceph

Using /srv/data caused SElinux alerts:
https://bugzilla.redhat.com/show_bug.cgi?id=1354488

This patch is an attempt to reduce or remove the alerts in our CI and
use /var/lib/ceph directory to store OSD data, like recommended by Ceph
documentation.

Change-Id: I4e6f31838ffb2b9dcde73fc06fbff78cd084b0af

manifests/ceph.pp

@@ -39,7 +39,7 @@ class openstack_integration::ceph {
       },
     },
     osds                      => {
-      '/srv/data' => {},
+      '/var/lib/ceph/data' => {},
     },
   }