gpg: Add status line PINENTRY_LAUNCHED.
* common/status.h (STATUS_PINENTRY_LAUNCHED): New. * g10/server.c (server_local_s): Add field allow_pinentry_notify. (option_handler): Add option "allow-pinentry-notify". (gpg_proxy_pinentry_notify): New. * g10/call-agent.c (default_inq_cb): Factor code out to the new function.