scd:p15: Make file selection more robust.
* scd/app-p15.c: Include host2net.h. (DEFAULT_HOME_DF): New. (select_and_read_binary): Replace slot by app. Change callers. Use select_ef_by_path. (select_and_read_record): ditto. (select_ef_by_path): Make use use the home_df. (parse_certid): Adjust for always set home_df. (print_tokeninfo_tokenflags): Ditto. (app_select_p15): Take the home_df from the FCI returned by select.
This uses modern APDUs and always selectd starting at the PCKS-15 home
DF. We could have made this much simpler but the goal is to keep
support for older cards although we can't test that easily.
- Signed-off-by: Werner Koch <wk@gnupg.org>