libbinder: Add ARpcServerTrusty API

Add an API for Rust code to create and call into
RpcServerTrusty objects.

Bug: 242243245
Test: trusty/vendor/google/aosp/scripts/build.py \
    --test "boot-test:com.android.trusty.rust.binder_rpc_test.test" \
    qemu-generic-arm64-test-debug
Change-Id: Iaaf255d9df59c62923dcc894d365e93beaec6c66