scd: Simplify the app_readkey parameters.
* scd/app-help.c (app_help_pubkey_from_cert): New. * scd/command.c (cmd_readkey): Refactor to use that new function and handle the --advanced flag only here. * scd/app.c (app_readkey): Remove parm advanced. * scd/app-common.h (struct app_ctx_s): Remove parm advanced from the readkey member. * scd/app-nks.c (do_readkey): Adjust for removed parm. * scd/app-piv.c (do_readkey): Ditto. * scd/app-openpgp.c (do_readkey): Ditto.
- Signed-off-by: Werner Koch <email@example.com>