audio: Add IBluetoothA2dp am: 7499a00c04 am: 9bd3729e12

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2459490

Change-Id: I019094d88714c70d1aa49bf7ceab7e892220027a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>