arm64: dts: rockchip: Add Radxa ROCK Pi 4B support

RockPI 4B has AP6256 Wifi/BT, so enable them in 4B dts
instead of enable in common dtsi.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Link: https://lore.kernel.org/r/20200807094826.12019-3-jagan@amarulasolutions.com


Signed-off-by: Heiko Stuebner <heiko@sntech.de>