Fix the CNI conflist of multitenancy and add the correct ipam type (#1373)

* Fix the CNI conflist of multitenancy and add the correct ipam type

* Adding the change to windows

cni/azure-linux-multitenancy.conflist

@@ -12,7 +12,7 @@
          "enableExactMatchForPodName": false,
          "enableSnatOnHost":true,
          "ipam":{
-            "type":"azure-vnet-ipam"
+            "type":"azure-cns"
          },
          "dns":{
             "nameservers":[]

cni/azure-windows-multitenancy.conflist

@@ -13,7 +13,7 @@
                 "portMappings": true
             },
             "ipam": {
-                "type": "azure-vnet-ipam"
+                "type": "azure-cns"
             },
             "dns": {
                 "Nameservers": [