Reduce duplication in Neutron reclass

  * Common definitions moved to neutron/control/cluster.yml
                               neutron/control/single.yml
  * neutron/control/cluster.yml and neutron/control/single.yml
    defined in conforming backend ones.

Change-Id: I9bf580c70a886db7188716f96d48f1d2a2d3a2a1
diff --git a/neutron/control/openvswitch/single.yml b/neutron/control/openvswitch/single.yml
index da8dee0..450ab07 100644
--- a/neutron/control/openvswitch/single.yml
+++ b/neutron/control/openvswitch/single.yml
@@ -1,5 +1,5 @@
 classes:
-- service.neutron.control.single
+- system.neutron.control.single
 - system.galera.server.database.neutron
 parameters:
   _param:
@@ -41,4 +41,4 @@
         protocol: ${_param:internal_protocol}
       message_queue:
         members:
-          - host: ${_param:openstack_message_queue_node01_address}
+          - host: ${_param:single_address}