audio: Add get param support and resolve compile errors

- Add get param support in AHAL for Direction of Arrival and Channel
  index from STHAL.
- Correct feature flag enable syntax and resolve compile errors.
- Remove codec loopback and add afe loopback mixer controls in mixer xml.
- Update sound_trigger_platform xml file.

CRs-Fixed: 2225936
Change-Id: I2e477013977a03a599d6bb4a52c66b897e967219