gpg: Allow decryption w/o public key but with correct card inserted.
* agent/command.c (cmd_readkey): Add option --no-data and special handling for $SIGNKEYID and $AUTHKEYID. * g10/call-agent.c (agent_scd_getattr): Create shadow keys for KEY-FPR output. * g10/skclist.c (enum_secret_keys): Automagically get a missing public key for the current card.
Backported-from-master: 50293ec2ebf2a997dbad9a47166d694efcc0709a)
- Signed-off-by: Werner Koch <wk@gnupg.org>