Define the AIDL interface for AuthGraph key exchange. am: 0e2495f107 am: 5c44262ee7 am: 65f40186c2

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2606133

Change-Id: I3dfbdabd04e87d2c56e3c0957aec00c0dad3bb7d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>