Fix nRF52 RS232 bridge baud initialization

src/helpers/bridges/RS232Bridge.cpp

@@ -17,7 +17,11 @@ void RS232Bridge::begin() {
   ((HardwareSerial *)_serial)->setPins(WITH_RS232_BRIDGE_RX, WITH_RS232_BRIDGE_TX);
 #elif defined(NRF52_PLATFORM)
   // Tested with RAK_4631 and T114
-  ((Uart *)_serial)->setPins(WITH_RS232_BRIDGE_RX, WITH_RS232_BRIDGE_TX);
+  Uart *uart = (Uart *)_serial;
+  if (*uart) {
+    uart->end();  // nRF52 begin() ignores baud and pin changes while already started
+  }
+  uart->setPins(WITH_RS232_BRIDGE_RX, WITH_RS232_BRIDGE_TX);
 #elif defined(RP2040_PLATFORM)
   ((SerialUART *)_serial)->setRX(WITH_RS232_BRIDGE_RX);
   ((SerialUART *)_serial)->setTX(WITH_RS232_BRIDGE_TX);