dt-bindings: mtd: rockchip: Prevent NAND chip unevaluated properties

List all the possible properties in the NAND chip as per the example and
set unevaluatedProperties to false in the NAND chip section.

Cc: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/linux-mtd/20230619092916.3028470-14-miquel.raynal@bootlin.com