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

iniparser: update to 4.2.4
https://github.com/void-linux/void-packages/pull/50534

Description:
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#### Testing the changes
- I tested the changes in this PR: **briefly**

Highlights:

- Dropped `iniparser-example` as it now builds example binaries which are neither useful nor allowed.
- ~~Modified pkgconfig includedir for compatiblity with `#include "iniparser.h"`~~
- ~~Disabled test installation~~
- Patched cava to use pkgconfig to find iniparser

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