arm64: dts: marvell: cp11x: Fix nand_controller node name according to YAML

Marvell NAND controller has now YAML to validate it's DT bindings, so
change the node name of cp11x DTSI as it is required by
nand-controller.yaml

Signed-off-by: Vadym Kochan <vadym.kochan@plvision.eu>
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>