treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 162

Based on 1 normalized pattern(s):

  gplv2 or later

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.654888175@linutronix.deSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sound/soc/atmel/atmel_wm8904.c

+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * atmel_wm8904 - Atmel ASoC driver for boards with WM8904 codec.
  *
  * Copyright (C) 2012 Atmel
  *
  * Author: Bo Shen <voice.shen@atmel.com>
- *
- * GPLv2 or later
  */
 
 #include <linux/clk.h>