Device Tree bindings for Armada DRM CRTC driver

Required properties:
 - compatible: value should be "marvell,dove-lcd".
 - reg: base address and size of the LCD controller
 - interrupts: single interrupt number for the LCD controller
 - port: video output port with endpoints, as described by graph.txt

Optional properties:

 - clocks: as described by clock-bindings.txt
 - clock-names: as described by clock-bindings.txt
	"axiclk" - axi bus clock for pixel clock
	"plldivider" - pll divider clock for pixel clock
	"ext_ref_clk0" - external clock 0 for pixel clock
	"ext_ref_clk1" - external clock 1 for pixel clock

Note: all clocks are optional but at least one must be specified.
Further clocks may be added in the future according to requirements of
different SoCs.

Example:

	lcd0: lcd-controller@820000 {
		compatible = "marvell,dove-lcd";
		reg = <0x820000 0x1000>;
		interrupts = <47>;
		clocks = <&si5351 0>;
		clock-names = "ext_ref_clk_1";
	};
