[automerger skipped] audio: Update README.md to add info about the AIDL version am: f3ef7fc9cb -s ours

am skip reason: Merged-In Ia627e3845a078e6a4c545b13a723a6c5a038c53b with SHA-1 6a9f697dfe is already in history

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2398052

Change-Id: I2c0f7a1160c4ccabe382b62f7ecbbd3924fcbe7c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>