agent: Modify agent_clear_passphrase to support an ext. password cache.
* agent/agent.h (agent_get_passphrase): Add arguments keyinfo and cache_mode. Update callers. * agent/call-pinentry.c (agent_get_passphrase): Add arguments keyinfo and cache_mode. If KEYINFO and CACHE_MODE describe a cachable key, then send SETKEYINFO to the pinentry.
- Signed-off-by: Neal H. Walfield <neal@g10code.com>