Support for multiple switches in cord subscriber test cases.
Configure the uplink olt device map for multiple switches correctly.

Change-Id: Ic263c445b2a14f688a6c08ea03e91b451bf37708
diff --git a/src/test/igmp/igmpTest.py b/src/test/igmp/igmpTest.py
index 55148a0..c25a8e4 100644
--- a/src/test/igmp/igmpTest.py
+++ b/src/test/igmp/igmpTest.py
@@ -84,7 +84,7 @@
     def setUpClass(cls):
           cls.olt = OltConfig(olt_conf_file = cls.olt_conf_file)
           cls.port_map, _ = cls.olt.olt_port_map()
-          OnosCtrl.cord_olt_config(cls.olt.olt_device_data())
+          OnosCtrl.cord_olt_config(cls.olt)
 
     @classmethod
     def tearDownClass(cls): pass