treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 372

Based on 1 normalized pattern(s):

  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
  the free software foundation version 2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 135 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531081036.435762997@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sound/usb/line6/midibuf.c

@@ -1,12 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Line 6 Linux USB driver
  *
  * Copyright (C) 2004-2010 Markus Grabner (grabner@icg.tugraz.at)
- *
- *	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 the Free Software Foundation, version 2.
- *
  */
 
 #include <linux/slab.h>