treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230

Based on 2 normalized pattern(s):

  this source code is licensed under the gnu general public license
  version 2 see the file copying for more details

  this source code is licensed under general public license version 2
  see

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 52 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.449021192@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

include/linux/crc-itu-t.h

@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  *	crc-itu-t.h - CRC ITU-T V.41 routine
  *
@@ -5,9 +6,6 @@
  *   Width 16
  *   Poly  0x1021 (x^16 + x^12 + x^15 + 1)
  *   Init  0
- *
- * This source code is licensed under the GNU General Public License,
- * Version 2. See the file COPYING for more details.
  */
 
 #ifndef CRC_ITU_T_H

include/linux/crc16.h

@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  *	crc16.h - CRC-16 routine
  *
@@ -7,9 +8,6 @@
  *   Init  0
  *
  * Copyright (c) 2005 Ben Gardner <bgardner@wabtec.com>
- *
- * This source code is licensed under the GNU General Public License,
- * Version 2. See the file COPYING for more details.
  */
 
 #ifndef __CRC16_H

include/linux/genalloc.h

@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * Basic general purpose allocator for managing special purpose
  * memory, for example, memory that is not managed by the regular
@@ -21,9 +22,6 @@
  * the allocator can NOT be used in NMI handler.  So code uses the
  * allocator in NMI handler should depend on
  * CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG.
- *
- * This source code is licensed under the GNU General Public License,
- * Version 2.  See the file COPYING for more details.
  */
 
 

include/linux/sha256.h

@@ -1,10 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  *  Copyright (C) 2014 Red Hat Inc.
  *
  *  Author: Vivek Goyal <vgoyal@redhat.com>
- *
- * This source code is licensed under the GNU General Public License,
- * Version 2.  See the file COPYING for more details.
  */
 
 #ifndef SHA256_H