drivers: soc: atmel: add spdx license identifier

Add SPDX-License-Identifier.
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
[nicolas.ferre@microhcip.com: remove license boilerplate now it's useless]
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/1611653376-24168-2-git-send-email-claudiu.beznea@microchip.com

drivers/soc/atmel/soc.c

+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (C) 2015 Atmel
  *
  * Alexandre Belloni <alexandre.belloni@free-electrons.com
  * Boris Brezillon <boris.brezillon@free-electrons.com
- *
- * This file is licensed under the terms of the GNU General Public
- * License version 2.  This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
- *
  */
 
 #define pr_fmt(fmt)	"AT91: " fmt

drivers/soc/atmel/soc.h

+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * Copyright (C) 2015 Atmel
  *
  * Boris Brezillon <boris.brezillon@free-electrons.com
- *
- * This file is licensed under the terms of the GNU General Public
- * License version 2.  This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
- *
  */
 
 #ifndef __AT91_SOC_H