Attempt to log message only in verbose mode

If the log level is not verbose, there is no need to attept to log
control messages at all.

app/src/controller.c

@@ -48,7 +48,10 @@ controller_destroy(struct controller *controller) {
 bool
 controller_push_msg(struct controller *controller,
                       const struct control_msg *msg) {
-    control_msg_log(msg);
+    if (sc_get_log_level() <= SC_LOG_LEVEL_VERBOSE) {
+        control_msg_log(msg);
+    }
+
     sc_mutex_lock(&controller->mutex);
     bool was_empty = cbuf_is_empty(&controller->queue);
     bool res = cbuf_push(&controller->queue, *msg);