kvm-ifup: Use /bin/bash

As reported by Ben Beuchler, kvm-ifup uses bash-specific constructs and
doesn't work with Ubuntu's default shell. We use bash all over the place
anyway, so changing the shebang line is the easiest solution.

Signed-off-by: Michael Hanselmann <hansmi@google.com>
Reviewed-by: René Nussbaumer <rn@google.com>

tools/kvm-ifup.in

-#!/bin/sh
+#!/bin/bash
 #
 
-# Copyright (C) 2011 Google Inc.
+# Copyright (C) 2011, 2012 Google Inc.
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by