Fixes OpenstackNetworking just sends warn msg when unsupported ovs-based sr-iov event occurs.

Change-Id: I375c55e55be2669224743e1412d02975989e30ad
diff --git a/apps/openstacknetworking/api/src/main/java/org/onosproject/openstacknetworking/api/Constants.java b/apps/openstacknetworking/api/src/main/java/org/onosproject/openstacknetworking/api/Constants.java
index e966db1..123cacc 100644
--- a/apps/openstacknetworking/api/src/main/java/org/onosproject/openstacknetworking/api/Constants.java
+++ b/apps/openstacknetworking/api/src/main/java/org/onosproject/openstacknetworking/api/Constants.java
@@ -57,6 +57,7 @@
     public static final String ANNOTATION_PORT_ID = "portId";
     public static final String ANNOTATION_CREATE_TIME = "createTime";
     public static final String ANNOTATION_SEGMENT_ID = "segId";
+    public static final String UNSUPPORTED_VENDOR = "unsupported_vendor";
 
     public static final int PRIORITY_TUNNEL_TAG_RULE = 30000;
     public static final int PRIORITY_FLOATING_INTERNAL = 42000;