lorawan: add initial LoRaWAN stack support

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

lora/lorawan/adaptor.go

@@ -0,0 +1,24 @@
+package lorawan
+
+import "tinygo.org/x/drivers/lora"
+
+var ActiveRadio lora.Radio
+
+func UseRadio(r lora.Radio) {
+	if ActiveRadio != nil {
+		panic("lorawan.ActiveRadio is already set")
+	}
+	ActiveRadio = r
+}
+
+func Join() error {
+	return nil
+}
+
+func SendUplink() error {
+	return nil
+}
+
+func ListenDownlink() error {
+	return nil
+}