[automerger skipped] Add attestation certificate parsing and validate for IC vts. am: 38ca6961e3 am: c7b50fed50 -s ours

am skip reason: Change-Id Ibe770e6eaf0b0018d60876926d824204e4eaf732 with SHA-1 cab019aae5 is in history

Change-Id: I3a41e3c5ed1fac3ba4dc8151d59a9a6a9c3a74db