treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_179.RULE

Based on the normalized pattern:

gpl header start do not alter or remove copyright notices or this
file header this program is free software you can redistribute it
and/or modify it under the terms of the gnu general public license
version 2 only as published by the free software foundation this
program is distributed in the hope that it will be useful but without
any warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
version 2 for more details (a copy is included in the license file
that accompanied this code) you should have received a copy of the
gnu general public license version 2 along with this program if not
see http://www gnu org/licenses please visit http://www xyratex
com/contact if you need additional information or have any questions
gpl header end

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference.

Reviewed-by: Allison Randal <allison@lohutok.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>