Revert SCD changes of 2010-05-03 (scd/ChangeLog 2010-03-17).
* scd/apdu.c (pcsc_no_service): Remove. (open_pcsc_reader_direct, open_pcsc_reader_wrapped): Remove pcsc_no_service support. (apdu_open_reader): Remove R_NO_SERVICE. * scd/apdu.h (apdu_open_reader): Remove R_NO_SERVICE. * scd/command.c (reader_disabled): Remove. (get_reader_slot): Follow the change of R_NO_SERVICE. (open_card, cmd_serialno, scd_command_handler): Remove reader_disabled support. * scd/sc-copykeys.c (main): Follow the change of R_NO_SERVICE.
Daemon should handle all possible cases. Even if such a difficult
case like reader_disabled, it should not exit.