Add files in third_party/fiat for Chromium to pick up.
Chromium's licenses.py is a little finicky.
Change-Id: I015a3565eb8f3cfecb357d142facc796a9c80888
Reviewed-on: https://boringssl-review.googlesource.com/24784
Reviewed-by: Adam Langley <agl@google.com>