Both btrfs_create_free_space_tree and btrfs_clear_free_space_tree
contain:

  if (ret)
          return ret;

  return 0;

The if statement is only false when ret equals zero, and since we return
zero in such cases, we can safely remove the branching.
Signed-off-by: NSahil Kang <sahil.kang@asilaycomputing.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>