Configuration for an SGX local assertion authority.
A 16-byte value that defines the attestation domain to which this SGX local
assertion authority belongs. This value is used to determine whether two
enclaves are running on the same hardware. SGX enclaves running on the same
hardware can use SGX local attestation.
An attestation domain is expected to be unique to a particular SGX machine
(i.e., two different SGX machines should have different attestation
domains). It can be thought of as the machine’s UUID.