dt-bindings: Add LEGO MINDSTORMS EV3 compatible specification

This adds the board level device tree specification for LEGO MINDSTORMS EV3

Acked-by: Rob Herring <[e-mail]>
Signed-off-by: David Lechner <[e-mail]>
Signed-off-by: Sekhar Nori <[e-mail]>

Documentation/devicetree/bindings/arm/davinci.txt

···
 Required root node properties:
     - compatible = "enbw,cmc", "ti,da850;
 
+LEGO MINDSTORMS EV3 (AM1808 based)
+Required root node properties:
+    - compatible = "lego,ev3", "ti,da850";
+
 Generic DaVinci Boards
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