New comment by newbluemoon on void-packages repository

https://github.com/void-linux/void-packages/pull/34029#issuecomment-969980443

Comment:
Added an upstream patch which removes piping into `onsgmls`, reading the file as a paramater instead. This seems to have been a residual from a long time ago and fixes half of the problem.

The test still fails because `docbook` ships a declaration which has `OMITTAG NO`. When set to `YES` the test passes. Debian for example completely patches out all `docbook` declarations and ships its own.

This seems to happen because the test sgml files are not valid according to the original docbook declaration and the way to go should be to fix the test sgml files. I will give it a shot, but until then, I think this PR is good to go as it is the test that’s broken. :)