Fixed to get OVS verion using Device.swVersion(), not by using annotation.

Change-Id: I6ae345941060319cdd5f4330e0536ae095603803
diff --git a/apps/openstacknetworkingui/src/main/java/org/onosproject/openstacknetworkingui/OpenstackNetworkingUiMessageHandler.java b/apps/openstacknetworkingui/src/main/java/org/onosproject/openstacknetworkingui/OpenstackNetworkingUiMessageHandler.java
index 86c4f44..3982d22 100644
--- a/apps/openstacknetworkingui/src/main/java/org/onosproject/openstacknetworkingui/OpenstackNetworkingUiMessageHandler.java
+++ b/apps/openstacknetworkingui/src/main/java/org/onosproject/openstacknetworkingui/OpenstackNetworkingUiMessageHandler.java
@@ -98,7 +98,6 @@
     private static final String FLOW_TRACE_RESULT = "flowTraceResult";
     private static final String SRC_DEVICE_ID = "srcDeviceId";
     private static final String DST_DEVICE_ID = "dstDeviceId";
-    private static final String SW_VERSION = "sw";
     private static final String OVS_VERSION_2_8 = "2.8";
     private static final String OVS_VERSION_2_6 = "2.6";
     private static final String FLAT = "FLAT";
@@ -429,7 +428,7 @@
         ObjectNode traceResultForwardJson = null;
 
         Device srcDevice = deviceService.getDevice(srcOpenstackNode.intgBridge());
-        if (srcDevice.annotations().value(SW_VERSION).startsWith(OVS_VERSION_2_8)) {
+        if (srcDevice.swVersion().startsWith(OVS_VERSION_2_8)) {
             traceResultForwardJson = Ovs28FlowTraceResultParser.flowTraceResultInJson(
                     traceResultForward.trim(), srcOpenstackNode.hostname());
         } else {