treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 243

Based on 1 normalized pattern(s):

  this file is licensed under the gpl v2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 3 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204654.634736654@linutronix.deSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/x86/kernel/eisa.c

+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * EISA specific code
- *
- * This file is licensed under the GPL V2
  */
 #include <linux/ioport.h>
 #include <linux/eisa.h>

arch/x86/kernel/idt.c

+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Interrupt descriptor table related code
- *
- * This file is licensed under the GPL V2
  */
 #include <linux/interrupt.h>
 

drivers/clocksource/acpi_pm.c

+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * linux/drivers/clocksource/acpi_pm.c
  *
@@ -12,8 +13,6 @@
  *
  * Based on parts of linux/drivers/acpi/hardware/hwtimer.c, timer_pit.c,
  * timer_hpet.c, and on Arjan van de Ven's implementation for 2.4.
- *
- * This file is licensed under the GPL v2.
  */
 
 #include <linux/acpi_pmtmr.h>