agent: Rework the trustlist reading code.
* agent/trustlist.c (read_one_trustfile): Replace es_fgets by es_read_line. List all errors before returning the first error. Print a status warning line. Add arg ctrl. (read_trustfiles): Add arg ctrl and pass on. (istrusted_internal): Ditto. (agent_listtrusted): Ditto.
- GnuPG-bug-id: T8078