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

pinebookpro: kernel: update to 6.1.9, base: drop firmware dependency, use ALSA UCM
https://github.com/void-linux/void-packages/pull/41062

Description:
~~Testing and review needed!~~

pinebookpro-base: drop firmware dep, use ALSA UCM

* Pinebook Pro kernel no longer supports video output via altmode dp, and
that was the only reason to install the linux-firmware dependency.
* Replace the asound.state file with a dependency on ALSA UCM, which now
supports the Pinebook Pro.

pinebookpro-kernel: update to 6.1.9

* Adopt.
* Bump to new LTS branch.
* Remove merged or obsolete DTS patches.
* Remove merged gamma LUT patchset.
* Remove hacky USB Type-C alternate mode DisplayPort patchset.
* Use zstd to compress modules

[ci skip]

[skip ci]

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