dt-bindings: arm: bcm: Add bindings for Buffalo WZR-1166DHP(2)

Add two more Northstar devices based on the BCM4708 SoC. Linux already
contains DTS files for both.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230602153657.11362-1-zajec5@gmail.com


Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>