Davinci SPI controller device bindings

Required properties:
- #address-cells: number of cells required to define a chip select
	address on the SPI bus. Should be set to 1.
- #size-cells: should be zero.
- compatible:
	- "ti,dm6441-spi" for SPI used similar to that on DM644x SoC family
	- "ti,da830-spi" for SPI used similar to that on DA8xx SoC family
- reg: Offset and length of SPI controller register space
- num-cs: Number of chip selects
- ti,davinci-spi-intr-line: interrupt line used to connect the SPI
	IP to the interrupt controller within the SoC. Possible values
	are 0 and 1. Manual says one of the two possible interrupt
	lines can be tied to the interrupt controller. Set this
	based on a specifc SoC configuration.
- interrupts: interrupt number mapped to CPU.
- clocks: spi clk phandle

Example of a NOR flash slave device (n25q032) connected to DaVinci
SPI controller device over the SPI bus.

spi0:spi@20BF0000 {
	#address-cells			= <1>;
	#size-cells			= <0>;
	compatible			= "ti,dm6446-spi";
	reg				= <0x20BF0000 0x1000>;
	num-cs				= <4>;
	ti,davinci-spi-intr-line	= <0>;
	interrupts			= <338>;
	clocks				= <&clkspi>;

	flash: n25q032@0 {
		#address-cells = <1>;
		#size-cells = <1>;
		compatible = "st,m25p32";
		spi-max-frequency = <25000000>;
		reg = <0>;

		partition@0 {
			label = "u-boot-spl";
			reg = <0x0 0x80000>;
			read-only;
		};

		partition@1 {
			label = "test";
			reg = <0x80000 0x380000>;
		};
	};
};