mtd: rawnand: vf610: Add an SPDX tag to replace the license text

Replace the license text by an SPDX tag.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

drivers/mtd/nand/raw/vf610_nfc.c

+// SPDX-License-Identifier: GPL-2.0+
 /*
  * Copyright 2009-2015 Freescale Semiconductor, Inc. and others
  *
@@ -10,11 +11,6 @@
  *
  * Based on original driver mpc5121_nfc.c.
  *
- * This 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.
- *
  * Limitations:
  * - Untested on MPC5125 and M54418.
  * - DMA and pipelining not used.