There is a new pull request by tibequadorian against master on the void-packages repository

https://github.com/tibequadorian/void-packages update-check-subpkgs
https://github.com/void-linux/void-packages/pull/36190

update_check: also work for subpackages
Currently `./xbps-src update-check` fails for many subpackages if the $pkgname or $pattern is not explicitly set in the update file, because it uses the subpackages $pkgname.

Example:
```
$ ./xbps-src update-check alsa-plugins-pulseaudio
NO VERSION found for alsa-plugins-pulseaudio
```

This PR tries to fix that by using $sourcepkg as the $pkgname.

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A patch file from https://github.com/void-linux/void-packages/pull/36190.patch is attached