Merge "Stub implementation for USB audio HAL." am: 2f97fbccb8 am: 86b3fa76b8

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2397735

Change-Id: I732080faa645215e8ad225ab5b55c05509c675f2
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>