Updating DHCP-l2-relay app version to 2.2.1
and voltha-onos to 4.1.6

Change-Id: I3bad721d6d922dfd6ef2b88b525889f4268e2527
diff --git a/.gitreview b/.gitreview
index 473a40c..01f99a3 100644
--- a/.gitreview
+++ b/.gitreview
@@ -3,4 +3,4 @@
 port=29418
 project=voltha-onos.git
 defaultremote=origin
-defaultbranch=master
+defaultbranch=voltha-2.5