Don't set TX timeout to 0 anymore for HW/USB CDC

Due to a change in the Espressif Arduino core, the TX timeout for the HW CDC
(used in the ESP32-S3, for example) must not be set to 0, as otherwise, an
integer underflow occurs.

Removing the TX timeout is not necessary anymore anyways, because it is now
detected when CDC is not active, and attempts to write will return immediately
until the host read something again. Only when the transmit buffer becomes
full initially, the default timeout of just 100ms takes effect once.

For USB CDC (used with the ESP32-S2, for example), the timeout is not relevant
either.

src/main.cpp

@@ -43,10 +43,8 @@ void setup()
 
     // Initialize serial output
     Serial.begin(SERIAL_BAUDRATE);
-#if ARDUINO_USB_CDC_ON_BOOT
+#if !ARDUINO_USB_CDC_ON_BOOT
-    Serial.setTxTimeoutMs(0);
+    // Only wait for serial interface to be set up when not using CDC
-    delay(100);
-#else
     while (!Serial)
         yield();
 #endif