Fixed bmv2-demo.py after updating bmv2.py switch constructor arguments

Change-Id: Id29d64f16d75cc0fefc017068fdd02cc15e816cc
diff --git a/tools/test/topos/bmv2-demo.py b/tools/test/topos/bmv2-demo.py
index ef0a124..e1ad7d9 100755
--- a/tools/test/topos/bmv2-demo.py
+++ b/tools/test/topos/bmv2-demo.py
@@ -75,7 +75,7 @@
                                                     netcfgDelay=0.5,
                                                     longitude=longitude,
                                                     latitude=latitude,
-                                                    pipeconfId=args.pipeconf_id)
+                                                    pipeconf=args.pipeconf_id)
 
         for i in range(1, args.size + 1):
             for j in range(1, args.size + 1):