examples/wifi: add unified example for tcpclient that compiles for all supported wifi adaptors

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

examples/wifi/tcpclient/wifinina.go

@@ -0,0 +1,36 @@
+//go:build wifinina
+// +build wifinina
+
+package main
+
+import (
+	"machine"
+	"tinygo.org/x/drivers/wifinina"
+)
+
+var (
+	// default interface for the Arduino Nano33 IoT.
+	spi = machine.NINA_SPI
+
+	// ESP32/ESP8266 chip that has the WIFININA firmware flashed on it
+	adaptor *wifinina.Device
+)
+
+func initAdaptor() *wifinina.Device {
+	// Configure SPI for 8Mhz, Mode 0, MSB First
+	spi.Configure(machine.SPIConfig{
+		Frequency: 8 * 1e6,
+		SDO:       machine.NINA_SDO,
+		SDI:       machine.NINA_SDI,
+		SCK:       machine.NINA_SCK,
+	})
+
+	adaptor = wifinina.New(spi,
+		machine.NINA_CS,
+		machine.NINA_ACK,
+		machine.NINA_GPIO0,
+		machine.NINA_RESETN)
+	adaptor.Configure()
+
+	return adaptor
+}