Update to test scripts to work with both ModemManager and Cromo

test/mm-set-carrier

 #!/usr/bin/python
 
+# Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
 import dbus
 import mm
 import sys
 
 def Usage(prog):
         print ("Usage: %s carrier "
                "<device path substring>") % prog
 
 if len(sys.argv) < 2 or len(sys.argv) > 3:
         Usage(sys.argv[0])
         sys.exit(1)
 
 carrier = sys.argv[1]
 
 if len(sys.argv) < 3:
         modem_pattern = ''
 else:
         modem_pattern = sys.argv[2]
 
-manager = mm.ModemManager()
-target = mm.PickOneModem(manager, modem_pattern)
-gobi_modem = manager.GobiModem(target)
+path = mm.PickOneModem(modem_pattern)
+gobi_modem = manager.GobiModem(path)
 gobi_modem.SetCarrier(carrier)