Updating the xconnect API to ONOS 2.2 format

Change-Id: I78295e9616cc40180ef8b96eb9052b7a7975644f
diff --git a/xos/synchronizer/steps/sync_fabric_crossconnect_service_instance.py b/xos/synchronizer/steps/sync_fabric_crossconnect_service_instance.py
index 5814c19..c03adab 100644
--- a/xos/synchronizer/steps/sync_fabric_crossconnect_service_instance.py
+++ b/xos/synchronizer/steps/sync_fabric_crossconnect_service_instance.py
@@ -131,7 +131,7 @@
 
         data = {"deviceId": o.switch_datapath_id,
                 "vlanId": o.s_tag,
-                "ports": [int(o.source_port), int(east_port)]}
+                "endpoints": [int(o.source_port), int(east_port)]}
 
         url = onos['url'] + '/onos/segmentrouting/xconnect'