There is an updated pull request by kawaiiamber against master on the void-packages repository

https://github.com/kawaiiamber/void-packages imlib2-heic
https://github.com/void-linux/void-packages/pull/27814

[WIP] New package: imlib2-heic-0.1.0
[WIP] as I'm not too confident if I included the licenses correctly. Also, the README says "for Debian, do `make` and copy `libheic.so`." However, there never seemed to be one after doing `make`, but they do have a makefile, so using `build_style=gnu-makefile`.

A patch file from https://github.com/void-linux/void-packages/pull/27814.patch is attached