New comment by pullmoll on void-packages repository

https://github.com/void-linux/void-packages/pull/24424#issuecomment-702594106

Comment:
Won't merge for now, since isl-0.22.1 is breaking things and we need to first work out whether to keep both packages, `isl` and `isl15`, and/or update which of these two. Breaking our compilers is no good idea, so closing this PR for now.