Remove Oculus Audio Spatializer

[bjornbytes]

This page says this:

The Oculus Spatializer Plugin has been replaced by the Meta XR Audio SDK and is now in end-of-life stage. It will not receive any further support beyond v47.

They recommend you use a new thing called "Meta XR Audio SDK", but this only appears to work with Unity and Unreal. I can't find a native version with a C API.

LÖVR's oculus spatializer was also added by mcc, who isn't around much anymore.

Considering all this, it's probably best to just remove the oculus spatializer.

With just phonon left, the spatializer system can be simplified a bit. There probably doesn't need to be a spatializer entry in conf.lua. LÖVR can just use phonon if the DLL is available and otherwise fall back to the simple spatializer. Phonon is also open source now, so it may be possible to remove a lot of the giant third party dependencies (embree, radeon rays, etc.) and get phonon down to a small size, which would allow us to include it by default.

[mcclure]

i'm not completely certain the oculus spatializer ever worked in the first place. there were large divergences between what the documentation claimed and the results i was actually getting :(