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>
diff --git a/lib/crc4.c b/lib/crc4.c
index 164ed94..e7e1779 100644
--- a/lib/crc4.c
+++ b/lib/crc4.c
@@ -1,8 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * crc4.c - simple crc-4 calculations.
- *
- * This source code is licensed under the GNU General Public License, Version
- * 2. See the file COPYING for more details.
  */
 
 #include <linux/crc4.h>