update libfido2 to 1.11.0, taking in just over a year of upstream
development. "looks ok" miod@ ok sthen@

NB. libfido2 major bump

sync with upstream libfido2 rev 2fa20b889, picking up ~7 months
of fixes and a few new APIs that we'd like to use in OpenSSH

ok 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@