audio: Add a helper class to simplify legacy HALs migration am: 43a85cfb2b am: 24d182487c am: 0b1e574946 am: 67e5cb4638

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2674340

Change-Id: I232f5b2582633dbf912d408eef00fb88b9b38965
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>