There's a merged pull request on the void-packages repository

ghc-bin: remove i686-musl support.
https://github.com/void-linux/void-packages/pull/31386

Description:
voidlinux.de has been shut down, so the distfiles can no longer be
accessed. Someone looking to re-add support will have to create a new
tarball.

Since we are here, add broken= case to catch template mistakes early.

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#### General
- [ ] This is a new package and it conforms to the [quality requirements](https://github.com/void-linux/void-packages/blob/master/Manual.md#quality-requirements)

#### Have the results of the proposed changes been tested?
- [ ] I use the packages affected by the proposed changes on a regular basis and confirm this PR works for me
- [ ] I generally don't use the affected packages but briefly tested this PR

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- [ ] I built this PR locally for these architectures (if supported. mark crossbuilds):
  - [ ] aarch64-musl
  - [ ] armv7l
  - [ ] armv6l-musl
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