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

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

Change-Id: Ie01a0cb16b925f6224c0c0d5268ee7d366c3038c