btrfs: replace GPL boilerplate by SPDX -- sources
Remove GPL boilerplate text (long, short, one-line) and keep the rest,
ie. personal, company or original source copyright statements. Add the
SPDX header.
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 53a0633..1b8a078 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -1,4 +1,5 @@
// SPDX-License-Identifier: GPL-2.0
+
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/spinlock.h>