hal: Fix WFD and voice call over USB concurrency

- If WFD framework occupies the AFE proxy, it may result unintended
  behavior while starting voice call over USB.
- Audio is always routed to the USB audio device when connected,
  even if WFD is connected. So no need to allow afe proxy port
  usage by WFD framework.
- Disallow the afe proxy port usage by external modules when
  AUDIO_DEVICE_OUT_USB_DEVICE is connected.

CRs-Fixed: 998488

Change-Id: I889be7f477ae3f7ad46757592a46f3d0e8eb41e2