Add Esp32 Serial USB JTAG support to uart driver

[mikee47]

This PR adds UART driver support for esp32 variants with an integrated USB JTAG/Serial port, such as esp32c3.
Requires ESP-IDF version 5.2 or later.

Example usage::

#ifdef UART_ID_SERIAL_USB_JTAG
  Serial.setPort(UART_ID_SERIAL_USB_JTAG);
#endif
Serial.begin(...);

See issue #2772