w32: Support fd passing through socket.
* src/assuan-socket-connect.c (_assuan_connect_finalize): Use w32_fdpass_send. Get peer's PID from the initial connection. * src/assuan-socket-server.c (assuan_init_socket_server): Use w32_fdpass_recv.
- GnuPG-bug-id: GnuPG-bug-id: T6236
- Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>