treewide: Replace GPLv2 boilerplate/reference with SPDX - gpl-2.0_30.RULE (part 2)

Based on the normalized pattern:

    this program is free software you can redistribute it and/or modify it
    under the terms of the gnu general public license as published by the
    free software foundation version 2  this program is distributed as is
    without any warranty of any kind whether express or implied without
    even the implied warranty of merchantability or fitness for a
    particular purpose see the gnu general public license for more details

extracted by the scancode license scanner the SPDX license identifier

    GPL-2.0-only

has been chosen to replace the boilerplate/reference.

Reviewed-by: Allison Randal <allison@lohutok.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/ptp/ptp_dte.c b/drivers/ptp/ptp_dte.c
index 82d31ba..8641fd0 100644
--- a/drivers/ptp/ptp_dte.c
+++ b/drivers/ptp/ptp_dte.c
@@ -1,15 +1,5 @@
-/*
- * Copyright 2017 Broadcom
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation version 2.
- *
- * This program is distributed "as is" WITHOUT ANY WARRANTY of any
- * kind, whether express or implied; without even the implied warranty
- * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- */
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright 2017 Broadcom
 
 #include <linux/err.h>
 #include <linux/io.h>