Handle the case where ONOS_APPS is not defined - needed for Jenkins

Change-Id: Ic587ebbb975b7ef285febfffd0e4414db0abc7ab
diff --git a/tools/dev/bash_profile b/tools/dev/bash_profile
index dd265b6..b47d286 100644
--- a/tools/dev/bash_profile
+++ b/tools/dev/bash_profile
@@ -240,6 +240,7 @@
         . $aux
         rm -f $aux
         # This is a hack to get master running on the existing cell infrastructure
+        apps=${ONOS_APPS:-}
         export ONOS_APPS=$ONOS_APPS,gui
         setPrimaryInstance 1 >/dev/null
         setMinorityMajority >/dev/null