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

https://github.com/sirikid/void-packages feature/collectd/prometheus
https://github.com/void-linux/void-packages/pull/26202

collectd: add prometheus build option
I will remove WIP commit before merge, I just don't know how to enable build with non-default options on CI.

A patch file from https://github.com/void-linux/void-packages/pull/26202.patch is attached