Add the DT node enabling Armada-8040-DB CPS SPI controller driver.

Add the SPI NAND flash device connected on the bus. Fill the MTD
partitions layout.
Signed-off-by: Christine Gharzuzi <chrisg@marvell.com>
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>