message: Add comment about TIOCGWINSZ .into().
diff: @@ -377,6 +377,8 @@ mod imp {
  pub fn stderr_width() -> Option<usize> {
  unsafe {
  let mut winsize: libc::winsize = mem::zeroed();
  + // The .into() here is needed for FreeBSD which defines TIOCGWINSZ
  + // as c_uint but ioctl wants c_ulong.
  if libc::ioctl(libc::STDERR_FILENO, libc::TIOCGWINSZ.into(), &mut winsize) < 0 {
  return None;
  }
  