arm64: dts: rockchip: Add SD card support to rock-5b

Add sdmmc support for Rock Pi 5B board.

Signed-off-by: Lucas Tanure <lucas.tanure@collabora.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://lore.kernel.org/r/20230529170532.59804-2-sebastian.reichel@collabora.com


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