Function librdkafka_sys::rd_kafka_conf_set_dr_msg_cb

pub unsafe extern fn rd_kafka_conf_set_dr_msg_cb(conf: *mut rd_kafka_conf_t,
                                                 dr_msg_cb: Option<unsafe extern fn(rk: *mut rd_kafka_t, rkmessage: *const rd_kafka_message_t, opaque: *mut c_void)>)