fido/mac: Change AAGUID for Touch ID self-authentication to all zeroes.

Touch ID previously used a non-zero AAGUID chosen by us. But WebAuthn
requires self-attestation to use an all-zero AAGUID value.

Also delete the unused |TouchIdAaguid| function.

Bug: 678128
Change-Id: I27bc82f7248d2c22ede773c0e6b010f56022d255
Reviewed-on: https://chromium-review.googlesource.com/1172911
Reviewed-by: Adam Langley <agl@chromium.org>
Reviewed-by: Balazs Engedy <engedy@chromium.org>
Commit-Queue: Balazs Engedy <engedy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#582888}
2 files changed