dt-bindings: mtd: mxc-nand: add missing compatible string and ref to nand-controller...

dt-bindings: mtd: mxc-nand: add missing compatible string and ref to nand-controller-legacy.yaml

Add compatible string fsl,imx51-nand, fsl,imx53-nand and fsl,imx35-nand.

Add missinge properties dmas and dma-names.

Change reg's maxItems to 2 because i.MX53 have addition NAND flash internal
buffer space.

Change ref to nand-controller-legacy.yaml allow legacy DT layout.

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>