Update simon's uk cells

Change-Id: Ia38870110491573920012bc5eb8a7ae3c2af77d0
diff --git a/tools/test/cells/simon-uk4 b/tools/test/cells/simon-uk4
index 03e4680..43808e5 100644
--- a/tools/test/cells/simon-uk4
+++ b/tools/test/cells/simon-uk4
@@ -38,7 +38,7 @@
 export ONOS_USER=sdn
 
 ## the apps we want activated at startup
-export ONOS_APPS="drivers,openflow,proxyarp,drivermatrix"
+export ONOS_APPS="drivers,openflow,proxyarp,drivermatrix,mlb"
 
 ## mininet VM
 export OCN="192.168.56.103"