scd: Fix access to list of cards (2/3).
* scd/app-common.h (card_reset, select_application): Simplify. * scd/app.c (card_reset, select_application): Simplify. * scd/command.c (do_reset): Follow the change. (open_card, open_card_with_request): Follow the change.
- Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>