controller/ha: disable keystone-manage bootstrap.

Because Overcloud Keystone resources are not managed by puppet-keystone
but by os-cloud-config, we need to let os-cloud-config managing keystone
bootstrap otherwise the Exec will fail since some data is already in
place.

Later, when Keystone resources will be managed by Puppet, drop this
parameter, because puppet-keystone is able to manage the boostrap
itself.

Change-Id: I027deaae5cf90c27a6b5e9d236ae61145cab3c3f
Closes-Bug: #1551501

puppet/manifests/overcloud_controller_pacemaker.pp

@@ -506,9 +506,12 @@
 if hiera('step') >= 3 {
 
   class { '::keystone':
-    sync_db        => $sync_db,
-    manage_service => false,
-    enabled        => false,
+    sync_db          => $sync_db,
+    manage_service   => false,
+    enabled          => false,
+    # TODO: when keystone resources will be managed by puppet-keystone
+    # for the overcloud, set enable_bootstrap to the default value (True).
+    enable_bootstrap => false,
   }
   include ::keystone::config