kernel: add SPDX-License-Identifier lines

Add SPDX-License-Identifier lines to some old kernel
files.

Signed-off-by: Tim Bird <tim.bird@sony.com>
Acked-by: Karim Yaghmour <karim.yaghmour@opersys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: tbird20d

kernel/cpu.c

@@ -1,7 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0
 /* CPU control.
  * (C) 2001, 2002, 2003, 2004 Rusty Russell
- *
- * This code is licenced under the GPL.
  */
 #include <linux/sched/mm.h>
 #include <linux/proc_fs.h>

kernel/relay.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Public API and common code for kernel->userspace relay file support.
  *
@@ -9,8 +10,6 @@
  * Moved to kernel/relay.c by Paul Mundt, 2006.
  * November 2006 - CPU hotplug support by Mathieu Desnoyers
  * 	(mathieu.desnoyers@polymtl.ca)
- *
- * This file is released under the GPL.
  */
 #include <linux/errno.h>
 #include <linux/stddef.h>