Fixing problems with rights for /var/lib/keystone/fernet-keys which should be 0750

Change-Id: I5b44255a1e7a91a2f248b3063f2364739a07ecd4
diff --git a/glusterfs/client/volume/keystone.yml b/glusterfs/client/volume/keystone.yml
index 39c5619..a93c0c1 100644
--- a/glusterfs/client/volume/keystone.yml
+++ b/glusterfs/client/volume/keystone.yml
@@ -12,6 +12,7 @@
           server: ${_param:keystone_glusterfs_service_host}
           user: keystone
           group: keystone
+          mode: 750
           opts: "defaults,backup-volfile-servers=${_param:glusterfs_node01_address}:${_param:glusterfs_node02_address}:${_param:glusterfs_node03_address}"
         keystone-credential-keys:
           path: /var/lib/keystone/credential-keys