sh: kernel: convert to SPDX identifiers

Update license to use SPDX-License-Identifier instead of verbose license
text.

Link: http://lkml.kernel.org/r/8736rccswn.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Cc: Rich Felker <dalias@libc.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/sh/kernel/machine_kexec.c

@@ -1,12 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * machine_kexec.c - handle transition of Linux booting another kernel
  * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
  *
  * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
  * LANDISK/sh4 supported by kogiidena
- *
- * This source code is licensed under the GNU General Public License,
- * Version 2.  See the file COPYING for more details.
  */
 #include <linux/mm.h>
 #include <linux/kexec.h>