ASoC: samsung: arndale: Convert to SPDX License Identifier

Replace GPL v2.0 license statements with SPDX license identifier.
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/samsung/arndale_rt5631.c

-/*
- *  arndale_rt5631.c
- *
- *  Copyright (c) 2014, Insignal Co., Ltd.
- *
- *  Author: Claude <claude@insginal.co.kr>
- *
- *  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+
+//
+// Copyright (c) 2014, Insignal Co., Ltd.
+//
+//  Author: Claude <claude@insginal.co.kr>
 
 #include <linux/module.h>
 #include <linux/platform_device.h>