Merge "audio: Add methods for controlling hw volume" am: 0ae51672

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2255291



Change-Id: Ie906f5d7a74c4af1e28ddcc79a9a05da768e6389
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>