Use power led for device status.
The status led behavior has already been fixed in af28d8a539fe
("ath79: add support for GL.iNet GL-AR750S") when porting the
device to ath79. This fixes it for ar71xx as well.
Signed-off-by: Jan Alexander <jan@nalx.net>
[minor commit title/message adjustments]
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
(cherry picked from commit d394c354ee0e8660f876889f6293803c581cbf85)
27e77922a1