Fix backward compatibility with single network engine definitions.

Change-Id: Ib022b5b3bfdac630312c97b06ca100b0ef4a1673
diff --git a/tests/pillar/master_contrail4_0.sls b/tests/pillar/master_contrail4_0.sls
index e703b2e..3f62f67 100644
--- a/tests/pillar/master_contrail4_0.sls
+++ b/tests/pillar/master_contrail4_0.sls
@@ -2,9 +2,6 @@
   common:
     cluster_domain: cluster.local
     cluster_name: cluster
-    network:
-      cnis:
-      - opencontrail
     hyperkube:
       image: hyperkube-amd64:v1.6.4-3
       hash: hnsj0XqABgrSww7Nqo7UVTSZLJUt2XRd
@@ -72,9 +69,8 @@
       address: 10.0.175.100
       allow_privileged: true
     network:
-      cnis:
-      - opencontrail
-      contrail:
+      opencontrail:
+        enabled: true
         version: 4.0
         private_ip_range: 10.150.0.0/16
         config: