Updating Copyright line to Open Networking Foundation

Change-Id: Icba96d7f39a065b53f34a6aeb71afd1f7d51f774
diff --git a/docs/external.xml b/docs/external.xml
index 0db71b3..41af63a 100644
--- a/docs/external.xml
+++ b/docs/external.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!--
-  ~ Copyright 2014-present Open Networking Laboratory
+  ~ Copyright 2014-present Open Networking Foundation
   ~
   ~ Licensed under the Apache License, Version 2.0 (the "License");
   ~ you may not use this file except in compliance with the License.