USB: serial: add copyright and license to quatech2

Add a copyright and license statement to the head of quatech.c source
file.  No code change here.
Signed-off-by: NBill Pemberton <wfp5p@virginia.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/serial/quatech2.c

 /*
  * usb-serial driver for Quatech USB 2 devices
  *
+ * Copyright (C) 2012 Bill Pemberton (wfp5p@virginia.edu)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
  *
  *  These devices all have only 1 bulk in and 1 bulk out that is shared
  *  for all serial ports.