btrfs: drop unused parameter from lock_extent_bits

We've always passed 0. Stack usage will slightly decrease.

Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 2907a77..23f396a 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -4161,7 +4161,7 @@
 
 	io_tree = &BTRFS_I(inode)->io_tree;
 
-	lock_extent_bits(io_tree, lockstart, lockend, 0, &cached_state);
+	lock_extent_bits(io_tree, lockstart, lockend, &cached_state);
 	ordered = btrfs_lookup_ordered_range(inode, lockstart, len);
 	if (ordered) {
 		btrfs_put_ordered_extent(ordered);