S40network: Be a little more pedantic

This will tell the end user what file this is for (Pluto or M2k), and then add a few more directions.

Signed-off-by: Robin Getz <robin.getz@analog.com>

board/pluto/S40network

@@ -75,8 +75,13 @@ create_system_files () {
 	fi
 
 	### /opt/config.txt ###
-	echo "# Device Configuration File"$'\r' > $CONF
-	echo "# Edit, Save and then Eject the USB Drive"$'\r' >> $CONF
+	echo "# $(cat /sys/firmware/devicetree/base/model | tr / -)"$'\r' > $CONF
+	echo "# Device Configuration File"$'\r' >> $CONF
+	echo "#   1. Open with an Editor"$'\r' >> $CONF
+	echo "#   2. Edit this file"$'\r' >> $CONF
+	echo "#   3. Save this file on the device USB drive"$'\r' >> $CONF
+	echo "#   4. Eject the device USB Drive"$'\r' >> $CONF
+	echo "# Doc: https://wiki.analog.com/university/tools/pluto/users/customizing"$'\r' >> $CONF
 	echo ""$'\r'>> $CONF
 	echo "[NETWORK]"$'\r' >> $CONF
 	echo "hostname = $HOSTNAME"$'\r' >> $CONF