New review comment by ahesford on void-packages repository

https://github.com/void-linux/void-packages/pull/34039#discussion_r1069536181

Comment:
In addition to using the file fetched from upstream (which requires `skip_extraction` to avoid confusing `xbps-src`), these kinds of file manipulations belong in `post_extract` so that it is possible to inspect the complete version of the source tree after `xbps-src -I extract <pkg>`. Also, avoid using absolute paths like `$XBPS_BUILDDIR` and instead rely on the fact that all of these functions will run in `${wkrsrc}`.

```suggestion
skip_extraction="FindSDL2.cmake"

post_extract() {
	cp ${XBPS_SRCDISTDIR}/${pkgname}-${version}/FindSDL2.cmake CMake/finders
}
```