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

opencl2-headers: install pkg-config and cmake cfg.
https://github.com/void-linux/void-packages/pull/45220

Description:
Switched to cmake provided by upstream.

I couldn't build some software that uses opencl due to pkg-config complaining about missing OpenCL-Headers. This fixed the issue for me.

Ping @ahesford WDYT?

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