audio HAL: Minimal example implementation am: df5adfde15 am: 88a81f47c6 am: 09c9ec4195 am: 4d9b179925

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2190587

Change-Id: I3b9a0209d69f9520067ea1863f62c412c670b758
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>