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

https://github.com/dkwo/void-packages O3xr
https://github.com/void-linux/void-packages/pull/42076

xrootd: update to 5.5.1
- I tested the changes in this PR: no
- I built this PR locally for my native architecture, (x86_64-musl)

Builds fine with openssl3 #37681 but note https://github.com/xrootd/xrootd/issues/1877
It performs no tests, so it is hard to tell @BenJarg 

A patch file from https://github.com/void-linux/void-packages/pull/42076.patch is attached