Fix breakage in vlan_learning example

Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>

examples/vlan_learning.py

@@ -122,7 +122,7 @@ for i in range(0, num_clients):
     # assign this client to the given worker
     idx = ipdb.interfaces["wrk%dp1" % worker_choice]["index"]
     mac = int(macaddr.replace(":", ""), 16)
-    ingress.update(c_ulonglong(mac), ifindex_leaf_t(idx, 0, 0))
+    ingress.update(ingress.Key(mac), ingress.Leaf(idx, 0, 0))
 
     cmd = ["bash", "-c", "for i in {1..8}; do curl 172.16.1.5 -o /dev/null; sleep 1; done"]
     client_processes.append(NSPopen(client.nl.netns, cmd))