Add message for setting attestation IDs.

Also remove some redundant EmptyKeymasterResponse tests.

Test: keymaster_tests
Bug: 190811656
Merged-In: If587a6bd28b8cbb0b11ac70a98c9841121836479
Change-Id: If587a6bd28b8cbb0b11ac70a98c9841121836479
2 files changed