Implement getInterfaceHash/Version for SoundTrigger

As the soundtrigger AIDL interface gets frozen for TM, java services
implementing the interface are required to implement getInterfaceHash
and getInterfaceVersion [1].

[1] https://source.android.com/devices/architecture/aidl/stable-aidl#new-meta-interface-methods

Bug: 225941299
Test: m
Change-Id: I5a7568cc081e6820b2041bc7ac34d1b0b4ff6009