Fixed 4th node tag issue; VTN hostManagementIface tag is now called "<node_name>_hostManagementIface_tag"

Change-Id: Ie0201923add8d522375db14c6d3d40a02a714882
diff --git a/mcord/make-vtn-external-yaml.sh b/mcord/make-vtn-external-yaml.sh
index 3239537..85df836 100644
--- a/mcord/make-vtn-external-yaml.sh
+++ b/mcord/make-vtn-external-yaml.sh
@@ -105,7 +105,7 @@
               relationship: tosca.relationships.MemberOfService
 
     # VTN hostManagementIface field for node $NODE
-    ${NODE}_dataPlaneIp_tag:
+    ${NODE}_hostManagementIface_tag:
       type: tosca.nodes.Tag
       properties:
           name: hostManagementIface