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

https://github.com/zlice/void-packages mupen64plus-update-to-2.5.9
https://github.com/void-linux/void-packages/pull/29692

mupen64plus: update to 2.5.9
#### Have the results of the proposed changes been tested?
- [ ] I use the packages affected by the proposed changes on a regular basis and confirm this PR works for me
- [x] I generally don't use the affected packages but briefly tested this PR
#### Does it build and run successfully? 
(Please choose at least one native build and, if supported, at least one cross build. More are better.)
- [x] I built this PR locally for my native architecture, (x86-64, libc)

#### Comments
2.5 was wobbling walls and textures in Mario64
Not sure if `nopie` is an issue, first time I've had to add that.

2.5 was from 2015, 2.5.9 is from 2019

edit:
updated linting
no clue on gpl spdx specifics

A patch file from https://github.com/void-linux/void-packages/pull/29692.patch is attached