dt-bindings: mtd: cadence: convert cadence-nand-controller.txt to yaml

Convert cadence-nand-controller.txt to yaml format.
Update cadence-nand-controller.txt to cdns,hp-nfc.yaml in MAINTAINER file.

Signed-off-by: Niravkumar L Rabara <niravkumar.l.rabara@intel.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>