test: Fix set-ipv4-method usage print

diff --git a/test/set-ipv4-method b/test/set-ipv4-method
index 576c803..0661537 100755 (executable)
--- a/test/set-ipv4-method
+++ b/test/set-ipv4-method
@@ -4,7 +4,7 @@ import sys
 import dbus
 
 def print_usage():
-       print "Usage: %s <service> [off|dhcp|manual <address> [netmask]]" % (sys.argv[0])
+       print "Usage: %s <service> [off|dhcp|manual <address> [netmask] [gateway]]" % (sys.argv[0])
 
 
 if (len(sys.argv) < 3):