Add nova service user metadata

Enable nova service user by default

Change-Id: I42ac5f7b5ae54fb20ee2f1fd822ac76ee87c938a
Related-Prod: PROD-27591
diff --git a/nova/compute/single.yml b/nova/compute/single.yml
index 836886e..16a3d06 100644
--- a/nova/compute/single.yml
+++ b/nova/compute/single.yml
@@ -73,6 +73,8 @@
         region: ${_param:openstack_region}
       barbican:
         enabled: ${_param:barbican_integration_enabled}
+      service_user:
+        enabled: ${_param:nova_service_user_enabled}
       message_queue:
         engine: rabbitmq
         host: ${_param:control_address}