Plumbed through the get_port_mode() API call

Change-Id: I68257b747a21a84f6898cdeaaa8169e928a3b355
diff --git a/util.py b/util.py
index 59f11ea..738eb00 100644
--- a/util.py
+++ b/util.py
@@ -101,6 +101,8 @@
                 ret = db.get_ports_by_current_vlan(data['vlan_id'])
             elif command == 'db.get_ports_by_base_vlan':
                 ret = db.get_ports_by_base_vlan(data['vlan_id'])
+            elif command == 'db.get_port_mode':
+                ret = db.get_port_mode(data['port_id'])
             elif command == 'db.get_ports_by_trunk':
                 ret = db.get_ports_by_trunk(data['trunk_id'])
             elif command == 'db.get_vlan_by_id':