Set PrivateDevices=false for CentOS7 Ceph deploys

We should aim to fix this up stream, but in order to get the builds
working again, we can work around this.

Change-Id: I963de91a672ff70f5461317560a7062a61c6799d
(cherry picked from commit 4c6f4d21a0)

playbooks/ceph-install.yml

@@ -60,6 +60,25 @@
            --setopt="Ceph-noarch.priority=50"
       when:
         - ansible_pkg_mgr == 'yum'
+    - name: Create systemd service directory
+      file:
+        path: "/etc/systemd/system/ceph-mon@.service.d/"
+        state: directory
+        group: "root"
+        owner: "root"
+        mode: "0755"
+      when:
+        - ansible_pkg_mgr == 'yum'
+        - ansible_service_mgr == 'systemd'
+    - name: Add systemd override for PrivateDevices
+      copy:
+        dest: "/etc/systemd/system/ceph-mon@.service.d/ceph-mon-systemd-overrides.conf"
+        content: |
+          [Service]
+          PrivateDevices=false
+      when:
+        - ansible_pkg_mgr == 'yum'
+        - ansible_service_mgr == 'systemd'
   roles:
     - role: "ceph-mon"
       tags: