…sagew, r=alexcrichton

`FormatMessageW` always inserts trailing `\r\n` to system messages which is a minor annoyance when they're fed to `Debug` but can break formatting with `Display`.

```rust
fn main() {
    use std::env;
    if let Err(err) = env::set_current_dir("???") {
        println!("{:#?}\n{}", err, err);
    }
}
```
```_
Error {
    repr: Os {
        code: 2,
        message: "The system cannot find the file specified.\r\n"
    }
}
The system cannot find the file specified.
 (os error 2)
```

- Successful merges: #27542, #27571, #27572, #27577, #27611, #27612, #27617, #27633, #27647, #27648, #27651
- Failed merges: