hal: Fix for transcode loopback issues

- Transcode loopback test app hangs at the end.
- As a fix, modify the release code sequence.
- Also add transcode loopback for 32khz pcm clips.

CRs-fixed: 2146098, 2142169
Change-Id: If0ca17ec58f7fc4715d75af11a1c6de707aac21b