mtd: rawnand: atmel: switch to SPDX license identifiers

Adopt the SPDX license identifiers to ease license compliance
management.
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

drivers/mtd/nand/raw/atmel/nand-controller.c

+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright 2017 ATMEL
  * Copyright 2017 Free Electrons
@@ -29,10 +30,6 @@
  *   Add Nand Flash Controller support for SAMA5 SoC
  *	Copyright 2013 ATMEL, Josh Wu (josh.wu@atmel.com)
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
  * A few words about the naming convention in this file. This convention
  * applies to structure and function names.
  *

drivers/mtd/nand/raw/atmel/pmecc.c

+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright 2017 ATMEL
  * Copyright 2017 Free Electrons
@@ -28,10 +29,6 @@
  *   Add Nand Flash Controller support for SAMA5 SoC
  *	Copyright 2013 ATMEL, Josh Wu (josh.wu@atmel.com)
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
  * The PMECC is an hardware assisted BCH engine, which means part of the
  * ECC algorithm is left to the software. The hardware/software repartition
  * is explained in the "PMECC Controller Functional Description" chapter in

drivers/mtd/nand/raw/atmel/pmecc.h

+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * © Copyright 2016 ATMEL
  * © Copyright 2016 Free Electrons
@@ -28,11 +29,6 @@
  *
  *    Add Nand Flash Controller support for SAMA5 SoC
  *        © Copyright 2013 ATMEL, Josh Wu (josh.wu@atmel.com)
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
  */
 
 #ifndef ATMEL_PMECC_H