[hwbcc] Client library

This change adds a client to implement the chip specific portions of
remote provisioning for usage by the keymaster TA. Specifically, it
exposes an interface for signing a MAC key and an interface for
retreiving the boot certificate chain. This functionality is explained
by the AIDL documentation for the IRemotelyProvisionedComponent HAL
interface in
android/hardware/interfaces/security/keymint/aidl/android/*/*.aidl

Bug: 194509629
Change-Id: I93a94f4bd09f5857bc42e78b950d0b6f963288a2
3 files changed