Change k8s network definitions structure.

Change-Id: Ibb460339e4f059efc1da7df587cad5f79a206068
diff --git a/classes/cluster/k8s-aio-calico/kubernetes/control.yml b/classes/cluster/k8s-aio-calico/kubernetes/control.yml
index 0616a0f..d26942b 100644
--- a/classes/cluster/k8s-aio-calico/kubernetes/control.yml
+++ b/classes/cluster/k8s-aio-calico/kubernetes/control.yml
@@ -51,9 +51,8 @@
       kubelet:
         address: ${_param:single_address}
       network:
-        cnis:
-        - calico
         calico:
+          enabled: true
           etcd:
             ssl:
               enabled: true