fixed minor bug in ptpd function
diff --git a/TestON/drivers/common/cli/onosdriver.py b/TestON/drivers/common/cli/onosdriver.py
index c8b974f..4bf6978 100644
--- a/TestON/drivers/common/cli/onosdriver.py
+++ b/TestON/drivers/common/cli/onosdriver.py
@@ -1034,7 +1034,7 @@
         '''
         try:
             self.handle.sendline("sudo ptpd "+str(args))
-            self.handle.expect([
+            i = self.handle.expect([
                 "Multiple",
                 "Error",
                 "\$"])