* certdump.c (print_sexp): Renamed to gpgsm_dump_serial, made
global.
(print_time): Renamed to gpgsm_dump_time, made global.
(gpgsm_dump_serial): Take a real S-Expression as argument and
print the first item.
* keylist.c (list_cert_colon): Ditto.
* keydb.c (keydb_search_issuer_sn): Ditto.
* decrypt.c (print_integer_sexp): Removed and made callers
use gpgsm_dump_serial.
* verify.c (print_time): Removed, made callers use gpgsm_dump_time.