unique_ptr fix

wled00/bus_manager.cpp

@@ -942,8 +942,8 @@ void BusManager::on() {
       uint8_t pins[2] = {255,255};
       if (bus->isDigital() && bus->getPins(pins)) {
         if (pins[0] == LED_BUILTIN || pins[1] == LED_BUILTIN) {
-          BusDigital *b = static_cast<BusDigital*>(bus);
-          b->begin();
+          BusDigital &b = static_cast<BusDigital&>(*bus);
+          b.begin();
           break;
         }
       }