scd:p15: Make it code work again for D-Trust cards.

* scd/app-p15.c (select_and_read_binary): Allow to skip the select.
(select_and_read_record): Return the statusword.  Silence error
message for SW_FILE_STRUCT.
(select_ef_by_path): Fix selection with a home_DF.
(read_first_record): Fallback to read_binary for CardOS and return
info about this.
(read_ef_prkdf): Use info from read_first_record to decide whether to
use record or binary mode.
(read_ef_pukdf): Ditto.
(read_ef_aodf): Ditto.
(read_ef_cdf): Ditto.  New arg cdftype for diagnostics.
(read_p15_info): Pass cdftype.

* scd/apdu.h (SW_FILE_STRUCT): New.
* scd/apdu.c (apdu_strerror): Map that one to a string.
* scd/iso7816.c (map_sw): and to a gpg-error.