[ONOS-2721] Fix the bug return info ports to port.

Change-Id: Ia9170a99e77eaf2d149bfb42e1c0b0da8570f782
diff --git a/apps/vtnweb/src/main/java/org/onosproject/vtnweb/resources/VirtualPortWebResource.java b/apps/vtnweb/src/main/java/org/onosproject/vtnweb/resources/VirtualPortWebResource.java
index b851a0f..1bcb291 100644
--- a/apps/vtnweb/src/main/java/org/onosproject/vtnweb/resources/VirtualPortWebResource.java
+++ b/apps/vtnweb/src/main/java/org/onosproject/vtnweb/resources/VirtualPortWebResource.java
@@ -99,7 +99,7 @@
         VirtualPort virtualPort = nullIsNotFound(get(VirtualPortService.class)

                 .getPort(VirtualPortId.portId(id)), VPORT_NOT_FOUND);

         ObjectNode result = new ObjectMapper().createObjectNode();

-        result.set("ports", new VirtualPortCodec().encode(virtualPort, this));

+        result.set("port", new VirtualPortCodec().encode(virtualPort, this));

         return ok(result.toString()).build();

     }