interfaces : switch userled on and off if AP mode is enabled

board/PSG/iot2000/rootfs_overlay/etc/network/interfaces

@@ -22,8 +22,10 @@ iface usb0 inet static
 
 iface wlan0 inet static
 	post-up hostapd -B /etc/hostapd/hostapd.conf
+	post-up echo 1 > /sys/class/leds/mpio_uart_led\:red\:user/brightness
 	address 192.168.10.200
 	netmask 255.255.255.0
 	broadcast 192.168.10.255
+	down echo 0 > /sys/class/leds/mpio_uart_led\:red\:user/brightness
 	down killall hostapd
-	down ip addr flush dev $IFACE
+	down ip addr flush dev wlan0