The -audiodev argument is replacing the QEMU_AUDIO_DRV env variable (and
its relations).
Sadly we still have to use the SDL_AUDIODRIVER env variable because that
wasn't mapped into QAPI schema.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>