Fix virtual router type values

Change-Id: I403e65cc571d33fbce81970c54909cc223ca1a8b
diff --git a/_modules/contrail.py b/_modules/contrail.py
index 3719653..f03ee33 100644
--- a/_modules/contrail.py
+++ b/_modules/contrail.py
@@ -146,6 +146,9 @@
     vnc_client = _auth(**kwargs)
     gsc_obj = _get_config(vnc_client)
     vrouter_objs = virtual_router_list(**kwargs)
+    router_types = ['tor-agent', 'tor-service-node', 'embedded']
+    if router_type not in router_types:
+        router_type = None
     if name in vrouter_objs:
         vrouter = virtual_router_get(name)
         vrouter_obj = vnc_client._object_read('virtual-router', id=vrouter[name]['uuid'])