There is an updated pull request by sug0 against master on the void-packages repository

https://github.com/sug0/void-packages mesa-vulkan-rpi
https://github.com/void-linux/void-packages/pull/34778

mesa: add Broadcom vulkan driver
<!-- Uncomment relevant sections and delete options which are not applicable -->

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

<!--
#### New package
- This new package conforms to the [quality requirements](https://github.com/void-linux/void-packages/blob/master/Manual.md#quality-requirements): **YES**|**NO**
-->

<!-- Note: If the build is likely to take more than 2 hours, please [skip CI](https://github.com/void-linux/void-packages/blob/master/CONTRIBUTING.md#continuous-integration)
and test at least one native build and, if supported, at least one cross build.
Ignore this section if this PR is not skipping CI.
-->

#### Local build testing
- I built this PR locally for my native architecture, aarch64

---

I created a new subpackage to build vulkan drivers for the Raspberry Pi 4. They seem to be working correctly, given the output of `vulkaninfo` from `Vulkan-Tools`, but I haven't actually tested any graphical workload, since `vkcube` is missing from `Vulkan-Tools` in `aarch64`.

P.S. -- I removed the update to 21.3.3 to keep this PR more feature isolated.

A patch file from https://github.com/void-linux/void-packages/pull/34778.patch is attached