update to libfido2 1.8.0; ok sthen@ "timing is fine" deraadt@

update to upstream libfido2 780ad3c25 (20120123)

install manual pages

crank major

feedback & ok jmc@ and naddy@

import libfido2 (git HEAD). This library allows communication with
U2F/FIDO2 devices over USB.

feedback and "start the churn" deraadt@