New issue by st3r4g on void-packages repository

https://github.com/void-linux/void-packages/issues/27286

Description:
`libGL` and friends being virtual gives some [unexpected behaviour](https://www.reddit.com/r/voidlinux/comments/kgeyvf/opengl_no_longer_working_after_a_clean_install/). Two options:
1) fix virtual package selection in xbps (how? who?)
2) make things easier/saner by getting rid of vpkg where possible. After all, `libglvnd` exists exactly for this purpose, that is avoiding multiple conflicting libGL library files. Vendors should use the `libglvnd` mechanism.

Option 2 means:
- Current `libGL` providers have to be removed: `nvidia340` (EOL) and `sunxi-mali` (?)
- New proprietary GL implementations not using `libglvnd` won't be accepted.

Thoughts?

@q66 @abenson