boards: explain how to use the wifinina driver with the default firmware as well as a link to espat

Signed-off-by: deadprogram <ron@hybridgroup.com>

Author: deadprogram

content/microcontrollers/arduino-nano33-iot.md

@@ -126,4 +126,6 @@ Once you have updated your Arduino Nano33 IoT board the first time, after that y
 
 You can use the USB port to the Arduino Nano33 IoT as a serial port. `UART0` refers to this connection.
 
-For information on how to use the built-in NINA-W102 wireless chip, please see the "espat" driver in the TinyGo drivers repository located at [https://github.com/tinygo-org/drivers/tree/release/espat](https://github.com/tinygo-org/drivers/tree/release/espat).
+For information on how to use the built-in NINA-W102 wireless chip with the default firmware, please see the "wifinina" driver in the TinyGo drivers repository located at [https://github.com/tinygo-org/drivers/tree/release/wifinina](https://github.com/tinygo-org/drivers/tree/release/wifinina).
+
+You can also use the Espressif ESP-AT firmware, although you will need to flash it yourself. Please see the "espat" driver in the TinyGo drivers repository located at [https://github.com/tinygo-org/drivers/tree/release/espat](https://github.com/tinygo-org/drivers/tree/release/espat).