Updated to return `INVALID_ARGUMENT` response code instead of
`SYSTEM_ERROR` while loading attest key.

While loading attest-key if it fails to find its blob or cert
then `INVALID_ARGUMENT` error reponse is returned instead of
`SYSTEM_ERROR`.
Bug: 254703846
Test: atest CtsKeystoreTestCases; atest keystore2_client_tests

Change-Id: Ie0d75c3bd99057b4c775e9c8f9dd91385cd6db81
2 files changed