PCI: Add SPDX GPL-2.0 to replace GPL v2 boilerplate

Add SPDX GPL-2.0 to all PCI files that specified the GPL version 2 license.

Remove the boilerplate GPL version 2 language, relying on the assertion in
b24413180f56 ("License cleanup: add SPDX GPL-2.0 license identifier to
files with no license") that the SPDX identifier may be used instead of the
full boilerplate text.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/pci/pcie/ptm.c b/drivers/pci/pcie/ptm.c
index bab8ac6..1071b8c 100644
--- a/drivers/pci/pcie/ptm.c
+++ b/drivers/pci/pcie/ptm.c
@@ -1,15 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * PCI Express Precision Time Measurement
  * Copyright (c) 2016, Intel Corporation.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope 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 for
- * more details.
  */
 
 #include <linux/module.h>