Support packet filtering for dynamips

Fix #1109

gns3server/compute/base_node.py

@@ -599,7 +599,7 @@ class BaseNode:
             yield from self._ubridge_send("bridge delete {name}".format(name=name))
 
     @asyncio.coroutine
-    def _update_ubridge_udp_connection(self, bridge_name, source_nio, destination_nio):
+    def update_ubridge_udp_connection(self, bridge_name, source_nio, destination_nio):
         yield from self._ubridge_apply_filters(bridge_name, destination_nio.filters)
 
     @asyncio.coroutine