debugfs: add SPDX identifiers to all debugfs files

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the debugfs files files with the correct SPDX license identifier
based on the license text in the file itself.  The SPDX identifier is a
legally binding shorthand, which can be used instead of the full boiler
plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/debugfs.h b/include/linux/debugfs.h
index 9f821a43bb0d..7beab3fd2f1a 100644
--- a/include/linux/debugfs.h
+++ b/include/linux/debugfs.h
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  *  debugfs.h - a tiny little debug file system
  *