ghc build failure on staging

## Issue description

`ghc` fails to build on staging

https://hydra.nixos.org/build/73972710

### Steps to reproduce

```sh
$ nix build -f https://github.com/NixOS/nixpkgs/archive/df062e3f7be4724973e4bcfa65e304b6a7ef746a.tar.gz ghc
```
