agent: Minor change to the KEYTOCARD command.
* agent/command.c (cmd_keytocard): Make timestamp optional. Use modern parser function. * agent/call-scd.c (agent_card_writekey): Rename an arg and for clarity return gpg_error_t instead of int. * agent/divert-scd.c (divert_writekey): Ditto.
- Signed-off-by: Werner Koch <wk@gnupg.org>