dt-bindings: thermal: samsung: Add SPDX license identifier

Replace GPL license statement with SPDX license identifier (GPL-2.0+).
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>

include/dt-bindings/thermal/thermal_exynos.h

+/* SPDX-License-Identifier: GPL-2.0+ */
 /*
  * thermal_exynos.h - Samsung EXYNOS TMU device tree definitions
  *
  *  Copyright (C) 2014 Samsung Electronics
  *  Lukasz Majewski <l.majewski@samsung.com>
- *
- * 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.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
  */
 
 #ifndef _EXYNOS_THERMAL_TMU_DT_H