ipq40xx: add get_status_led to diag.sh

This commit adds the get_status_led method to diag.sh, which sets the
boot-led as status-led for scripts using this method to get a
status-led.

This method is used platform-independent in downstream project gluon to
set the LED used to indicate the config-mode.

Signed-off-by: David Bauer <mail@david-bauer.net>

target/linux/ipq40xx/base-files/etc/diag.sh

@@ -7,6 +7,10 @@ failsafe="$(get_dt_led failsafe)"
 running="$(get_dt_led running)"
 upgrade="$(get_dt_led upgrade)"
 
+get_status_led() {
+	status_led="$boot"
+}
+
 set_state() {
 	status_led="$boot"