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

Replace waf with waf3 where applicable
https://github.com/void-linux/void-packages/pull/21227

Description:
~Intent is to remove waf build style.~

Most of remaining packages use waf 1.6 that is incompatible with python3.

- [x] Ardour 6 will use newer waf.
- [x] lilv builds but installs some python modules that are to be checked for py3 compatibility.

~flowcanvas is unmaintained and replacement is packaged, so will be removed, as well as already broken packages.~
~ladish won't use build style.~