devicetree: add Itead vendor prefix

Add the "itead" vendor prefix for ITEAD Intelligent Systems Co.Ltd.
Signed-off-by: Marcus Cooper <codekipper@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/vendor-prefixes.txt

@@ -159,6 +159,7 @@ iom	Iomega Corporation
 isee	ISEE 2007 S.L.
 isil	Intersil
 issi	Integrated Silicon Solutions Inc.
+itead	ITEAD Intelligent Systems Co.Ltd
 jdi	Japan Display Inc.
 jedec	JEDEC Solid State Technology Association
 karo	Ka-Ro electronics GmbH