Fix refines_xchg_r

Seems like @dfrumin did the exact same fix on master now (538a5d7f).

closed

Hi @NiklasM ! thanks a lot for your PR, I am very bad at managing this kind of stuff / software engineering so I totally missed your PR, but it could have saved me a lot of time i appreciate you taking time to make it. please feel free to bug and ping me if i am ignoring your PRs/issues next time