Adding RSA PKCS1 and EC SEC 1 formats to read_attestation_key

read_attestation_key now will try first to parse a key as if it was
a PKCS8 key, but if it fails it will try to parse an RSA key as a
PKCS1 encoded key and a EC key as a SEC 1 encoded key.

Bug: 258602662
Test: Build.py, run keymint TA unittests
Change-Id: I8ee45e3a8ea51e3cfd047dc797282a0c5e4de3eb
3 files changed