ASoC: wm1133-ev1: Switch to SPDX identifier

Adopt the SPDX license identifier headers to ease license compliance
management.
Signed-off-by: Andra Danciu <andradanciu1997@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/fsl/wm1133-ev1.c

-/*
- *  wm1133-ev1.c - Audio for WM1133-EV1 on i.MX31ADS
- *
- *  Copyright (c) 2010 Wolfson Microelectronics plc
- *  Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
- *
- *  Based on an earlier driver for the same hardware by Liam Girdwood.
- *
- *  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;  either version 2 of the  License, or (at your
- *  option) any later version.
- */
+// SPDX-License-Identifier: GPL-2.0+
+//
+//  wm1133-ev1.c - Audio for WM1133-EV1 on i.MX31ADS
+//
+//  Copyright (c) 2010 Wolfson Microelectronics plc
+//  Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+//
+//  Based on an earlier driver for the same hardware by Liam Girdwood.
 
 #include <linux/platform_device.h>
 #include <linux/clk.h>