watchdog: ibmasr: Replace GPL license notice with SPDX identifier

Replace unversioned GPL license notice with appropriate SPDX license
identifier, which is GPL 1.0+.

Cc: Andrey Panin <pazke@donpac.ru>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lkml.kernel.org/r/20230517072140.1086660-3-bagasdotme@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

drivers/watchdog/ibmasr.c

@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-1.0+
 /*
  * IBM Automatic Server Restart driver.
  *
@@ -6,8 +7,6 @@
  * Based on driver written by Pete Reynolds.
  * Copyright (c) IBM Corporation, 1998-2004.
  *
- * This software may be used and distributed according to the terms
- * of the GNU Public License, incorporated herein by reference.
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt