Read the VMi object before adding pbf rules

It is possible that vmi->RI links have changed. If we don't refresh, we may not
add the pbf rule if it is already present in the stale copy.

Change-Id: Ia72436aff6abdf654f05a5ec7e50ba06bb887dc3
Closes-Bug: 1509063

src/config/schema-transformer/to_bgp.py

@@ -1877,6 +1877,7 @@ def _create(self, si_info):
     def add_pbf_rule(self, vmi, ri1, ri2, ip_address, vlan):
         if vmi.service_interface_type not in ["left", "right"]:
             return
+        vmi.obj = _vnc_lib.virtual_machine_interface_read(id=vmi.uuid)
         refs = vmi.obj.get_routing_instance_refs() or []
         ri_refs = [ref['to'] for ref in refs]