add self dns record to hosts

I'll test it on k8s_ha_contrail and add to other labs later.

Change-Id: I0c8b343c3c9c5c11b6a6fc70248c27874f40a379
diff --git a/classes/cluster/k8s_ha_contrail/infra/init.yml b/classes/cluster/k8s_ha_contrail/infra/init.yml
index 166a17b..a624371 100644
--- a/classes/cluster/k8s_ha_contrail/infra/init.yml
+++ b/classes/cluster/k8s_ha_contrail/infra/init.yml
@@ -15,6 +15,11 @@
   linux:
     network:
       host:
+        self:
+          address: ${_param:single_address}
+          names:
+          - ${linux:system:name}
+          - ${linux:system:name}.${linux:system:domain}
         cfg01:
           address: ${_param:infra_config_address}
           names: