ARM: dts: BCM5301X: Add DT for Luxul XAP-1410

Luxul XAP-1410 in a dual-band access point device based on BCM47081 with
serial flash. It has 3 LEDs and just one (reset) button.

Signed-off-by: Dan Haab <dhaab@luxul.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>