Add p4 trellis job for 2.1

Change-Id: I02ed281ec311a8f1113e5061d26999f85a191a71
diff --git a/jjb/onos/onos-verify.yaml b/jjb/onos/onos-verify.yaml
index 11eea17..af3cd83 100644
--- a/jjb/onos/onos-verify.yaml
+++ b/jjb/onos/onos-verify.yaml
@@ -950,6 +950,7 @@
     build-node: 'ubuntu16.04-basebuild-8c-15g'
 
     stream:
+      - 'onos-2.1'
       - 'master'
 
     jobs: