Fixes for using the new efx code with macOS and Linux. This PR also changes linux to use the T3D supplied openal-soft instead of the system supplied one, also changes macOS to use the T3D openal-soft instead of the now deprecated apple opeanl version (that didn't support efx extensions anyway). All 3 platforms now use the same openal-soft build.
Fixes for using the new efx code with macOS and Linux. This PR also changes linux to use the T3D supplied openal-soft instead of the system supplied one, also changes macOS to use the T3D openal-soft instead of the now deprecated apple opeanl version (that didn't support efx extensions anyway). All 3 platforms now use the same openal-soft build.