docs: add Arduino Nano to list of supported boards

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

README.md

@@ -43,7 +43,7 @@ See the [getting started instructions](https://tinygo.org/getting-started/) for
 
 You can compile TinyGo programs for microcontrollers, WebAssembly and Linux.
 
-The following 25 microcontroller boards are currently supported:
+The following 26 microcontroller boards are currently supported:
 
 * [Adafruit Circuit Playground Express](https://www.adafruit.com/product/3333)
 * [Adafruit Circuit Playground Bluefruit](https://www.adafruit.com/product/4333)
@@ -55,6 +55,7 @@ The following 25 microcontroller boards are currently supported:
 * [Adafruit PyBadge](https://www.adafruit.com/product/4200)
 * [Adafruit PyPortal](https://www.adafruit.com/product/4116)
 * [Adafruit Trinket M0](https://www.adafruit.com/product/3500)
+* [Arduino Nano](https://store.arduino.cc/arduino-nano)
 * [Arduino Nano33 IoT](https://store.arduino.cc/nano-33-iot)
 * [Arduino Uno](https://store.arduino.cc/arduino-uno-rev3)
 * [BBC micro:bit](https://microbit.org/)