[CORD-3191] Remove old pmc-olt ref. Replace with voltha

Change-Id: I661c00526f377e99aac25037276019e1f724c36e
diff --git a/src/test/utils/OnosCtrl.py b/src/test/utils/OnosCtrl.py
index 3aa09ba..dc4f05c 100644
--- a/src/test/utils/OnosCtrl.py
+++ b/src/test/utils/OnosCtrl.py
@@ -277,7 +277,7 @@
         return False, 400
 
     @classmethod
-    def config_device_driver(cls, controller = None, dids = None, driver = 'pmc-olt'):
+    def config_device_driver(cls, controller = None, dids = None, driver = 'voltha'):
         driver_apps = ('org.onosproject.drivers', 'org.onosproject.openflow-base',)
         if dids is None:
             dids = cls.get_device_ids(controller = controller)