ARM: dts: rockchip: Add Radxa Dalang Carrier board

ARM: dts: rockchip: Add Radxa Dalang Carrier board

Carrier board often referred as baseboard. For making
complete SBC or any other industrial boards, these
carrier boards will be used with associated SOMs.

Radxa has Dalang carrier board which supports on-board
peripherals, ports like USB-2.0, USB-3.0, HDMI, MIPI DSI/CSI,
eDP, Ethernet, WiFi, PCIe, USB-C, 40-Pin GPIO header and etc.

Right now Dalang carrier board is used with two SBC-variants:
Rock Pi N10 => VMARC RK3399Por SOM + Dalang carrier board
Rock Pi N8  => VMARC RK3288 SOM + Dalang carrier board(+codec)

So add this carrier board dtsi as a separate file in
ARM directory, so-that the same can reuse it in both
rk3288, rk3399pro variants of Rockchip SOMs.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Link: https://lore.kernel.org/r/20191216174711.17856-4-jagan@amarulasolutions.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>