Revert "make test: fix broken interfaces"

This reverts commit d5c60b96a3fd93916fc4af5c8d6d25625c28242e.

Change-Id: I3632b9c3f76c615aee897f28f76d094e7031e689
Signed-off-by: Ole Troan <ot@cisco.com>
diff --git a/test/test_ip4_irb.py b/test/test_ip4_irb.py
index 460cb43..bbec7ca 100644
--- a/test/test_ip4_irb.py
+++ b/test/test_ip4_irb.py
@@ -54,7 +54,7 @@
 
         # create 3 pg interfaces, 1 loopback interface
         cls.create_pg_interfaces(range(3))
-        cls.create_loopback_interfaces(1)
+        cls.create_loopback_interfaces(range(1))
 
         cls.interfaces = list(cls.pg_interfaces)
         cls.interfaces.extend(cls.lo_interfaces)