scd:p15: Handle duplicate certificate ids.
* scd/app-p15.c (struct app_local_s): Add field cdf_dup_counter. (objid_in_cdflist_p): New. (read_p15_info): Clear the counter. (read_ef_cdf): Detect and fix duplicate IDs.
- GnuPG-bug-id: T7001
- Reported-by: Mario Haustein <mario.haustein@hrz.tu-chemnitz.de>