New comment by pullmoll on void-packages repository

https://github.com/void-linux/void-packages/pull/21340#issuecomment-620099946

Comment:
I don't think there actually are differences as there's no reference to the _FILEOFFSET_BITS which is or may be 32 for i686, while it's always 64 for i686-musl. That's an anachronism anyway.

So I think we could just remove the `*-musl.conf` files and strip the suffix from the target, i.e. `${XBPS_TARGET_MACHIN%-musl}.conf` in the template.