dt-bindings: add power-domain header for RK3568 SoCs

According to a description from TRM, add all the power domains

Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com>
Reviewed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Johan Jonker <jbx6244@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210417112952.8516-11-jbx6244@gmail.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>