Add nova service user metadata

Enable nova service user by default

Change-Id: I42ac5f7b5ae54fb20ee2f1fd822ac76ee87c938a
Related-Prod: PROD-27591
diff --git a/nova/compute_ironic/cluster.yml b/nova/compute_ironic/cluster.yml
index 4d49198..6d827b6 100644
--- a/nova/compute_ironic/cluster.yml
+++ b/nova/compute_ironic/cluster.yml
@@ -26,6 +26,8 @@
         password: ${_param:keystone_nova_password}
         tenant: service
         protocol: ${_param:cluster_internal_protocol}
+      service_user:
+        enabled: ${_param:nova_service_user_enabled}
       message_queue:
         engine: rabbitmq
         port: 5672