btrfs-progs: use NULL instead of 0

These were mostly in option structs but there were a few gross string
pointer arguments given as 0.

Signed-off-by: Zach Brown <zab@redhat.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/btrfs.c b/btrfs.c
index 6c172a82..630dc085 100644
--- a/btrfs.c
+++ b/btrfs.c
@@ -257,7 +257,7 @@ static const struct cmd_group btrfs_cmd_group = {
 		{ "replace", cmd_replace, NULL, &replace_cmd_group, 0 },
 		{ "help", cmd_help, cmd_help_usage, NULL, 0 },
 		{ "version", cmd_version, cmd_version_usage, NULL, 0 },
-		{ 0, 0, 0, 0, 0 }
+		NULL_CMD_STRUCT
 	},
 };