Default Console UART Rx Tx defined in HardwareSerial Constructor

[SuGlider]

Description of Change

ESP32 SoCs attach RX and TX pins in boot time, conneting those GPIOs to IOMUX or GPIO Matrix.
Therefore, if the user calls HardwareSerial::setPins() or HardwareSerial::end() with no previous HardwareSerial::begin(),
those default already attached pins won't be detached, preventing them to be used for other purpose.

This PR shall be merged along with #8619 in order to make full effect with HardwareSerial::setPins()

Tests scenarios

void setup() {
  ets_printf("\nThis Line is printed fine because it uses TX Pin attached in Boot Time.\n\n");
  Serial.end();                 // shall detach default UART0 RX/TX
  ets_printf("1:: This Log line shall not be displayed!\n"); // using IDF console ets_printf() -- TX unattached!
  
  Serial.begin(115200);  // set default RX/TX pin because nothing was defined in the call
  Serial.println("2:: This line shall be seen.");
  Serial.flush();

  Serial.setPins(-1, 2);    // shall set UART0 to GPIO2 and detach default TX -- DEPENDS on MERGING #8619 
  Serial.println("3:: This line shall NOT be seen.");  // default TX is no longer attached
  Serial.flush();
  
  Serial.end();
  Serial.setPins(-1, 2); // it has not effect because Serial is ended... 
  Serial.begin(115200);  // This shall not set default TX pin because the previous setPin() was executed
  Serial.println("4:: This line shall NOT be seen.");  // default TX is no longer attached
  Serial.flush();
}

void loop() {}

Related links

Closes #8324
Closes #8573

[me-no-dev]

if this is for UART0 only, would it not be safer to keep the old signature and handle the default pins in the constructor?

[SuGlider]

Yes, this is a better way, less intrusive.

[SuGlider]

@me-no-dev - This PR will remain as draft. Please review and merge #8629 to 2.0.13