Fixing ServiceInstance.eastbound_service_instances method in convienence_methods

Change-Id: I76a8db7202f45b137fe4a7a38df87c1158e939ff
diff --git a/xos/xos_client/xosapi/convenience/serviceinstance.py b/xos/xos_client/xosapi/convenience/serviceinstance.py
index b6523d8..ffb6bc3 100644
--- a/xos/xos_client/xosapi/convenience/serviceinstance.py
+++ b/xos/xos_client/xosapi/convenience/serviceinstance.py
@@ -43,7 +43,7 @@
 
     @property
     def eastbound_service_instances(self):
-        links = self.subscriber_links.all()
+        links = self.subscribed_links.all()
         instances = []
         for link in links:
             instances.append(link.provider_service_instance.leaf_model)