message: Fix redox readlink
diff: @@ -894,26 +894,10 @@ impl Pal for Sys {
  }
  fn readlink(pathname: &CStr, out: &mut [u8]) -> ssize_t {
  - let file = match File::open(
  - pathname,
  - fcntl::O_PATH | fcntl::O_SYMLINK | fcntl::O_CLOEXEC,
  - ) {
  - Ok(ok) => ok,
  + match File::open(pathname, fcntl::O_RDONLY | fcntl::O_SYMLINK | fcntl::O_CLOEXEC) {
  + Ok(file) => Self::read(*file, out),
  Err(_) => return -1,
  - };
  -
  - if out.is_empty() {
  - return 0;
  }
  -
  - let len = out.len();
  - let read = e(syscall::fpath(*file as usize, &mut out[..len - 1]));
  - if (read as c_int) < 0 {
  - return -1;
  - }
  - out[read as usize] = 0;
  -
  - 0
  }
  fn rename(oldpath: &CStr, newpath: &CStr) -> c_int {
  