Change k8s network definitions structure.

Change-Id: Ibb460339e4f059efc1da7df587cad5f79a206068
diff --git a/classes/cluster/k8s-aio-contrail/kubernetes/compute.yml b/classes/cluster/k8s-aio-contrail/kubernetes/compute.yml
index e8803e5..a5559f4 100644
--- a/classes/cluster/k8s-aio-contrail/kubernetes/compute.yml
+++ b/classes/cluster/k8s-aio-contrail/kubernetes/compute.yml
@@ -36,8 +36,8 @@
   kubernetes:
     pool:
       network:
-        cnis:
-        - opencontrail
+        opencontrail:
+          enabled: true
     common:
       hyperkube:
         image: ${_param:kubernetes_hyperkube_image}