Add 'system.galera.server.database.neutron' on database nodes

Related to https://gerrit.mcp.mirantis.com/#/c/29231/

Change-Id: I7b322d0b86a3d5fae6da1f828599530cf0626d50
diff --git a/classes/cluster/virtual-offline-pike-ovs/openstack/control.yml b/classes/cluster/virtual-offline-pike-ovs/openstack/control.yml
index 5fdb7da..7933f6e 100644
--- a/classes/cluster/virtual-offline-pike-ovs/openstack/control.yml
+++ b/classes/cluster/virtual-offline-pike-ovs/openstack/control.yml
@@ -35,6 +35,7 @@
 - system.galera.server.database.heat
 - system.galera.server.database.keystone
 - system.galera.server.database.nova
+- system.galera.server.database.neutron
 - system.galera.server.database.designate
 - system.haproxy.proxy.listen.openstack.nova-placement
 - cluster.virtual-offline-pike-ovs