PXA3xx NAND DT bindings

Required properties:

 - compatible:		Should be "marvell,pxa3xx-nand"
 - reg: 		The register base for the controller
 - interrupts:		The interrupt to map
 - #address-cells:	Set to <1> if the node includes partitions

Optional properties:

 - marvell,nand-enable-arbiter:	Set to enable the bus arbiter
 - marvell,nand-keep-config:	Set to keep the NAND controller config as set
				by the bootloader
 - num-cs:			Number of chipselect lines to usw

Example:

	nand0: nand@43100000 {
		compatible = "marvell,pxa3xx-nand";
		reg = <0x43100000 90>;
		interrupts = <45>;
		#address-cells = <1>;

		marvell,nand-enable-arbiter;
		marvell,nand-keep-config;
		num-cs = <1>;

		/* partitions (optional) */
	};