Show nicer serial numbers for OpenPGP cards and Yubikeys

* For OpenPGP card serial number add a space between manufacturer id and
  card id (as printed on actual OpenPGP cards and as done by gpg-agent
  when asking for a card)
* For Yubikey tokens show Yubikey id printed on the tokens (working
  around a bug in scdaemon)

GnuPG-bug-id: 5066