HAL support (macOS)

[fasterthanlime]

Overland is a wwise game, it's terribly slow in my test VM though so it'd take me a long time to figure out exactly what it's using - but in my last test it didn't seem like the coreaudio hooks were called.

Maybe someone whose mac hardware didn't die on them unexpectedly can help research this?

[fasterthanlime]

Looks like WWise is using AkSoundEngine which in turns uses HAL (IOAudioDevice etc.) instead of the AudioUnit stuff we're hooking - see https://developer.apple.com/library/content/documentation/DeviceDrivers/Conceptual/WritingAudioDrivers/AudioOnMacOSX/AudioOnMacOSX.html