btrfs: Use btrfs_space_info_used instead of opencoding it

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Nikolay Borisov 2017-06-14 11:35:34 +03:00 • committed by David Sterba
commit 0eee8a494e