dt-bindings: Add vendor prefix for Avnet, Inc.

"Avnet, Inc. is one of the world's largest distributors of electronic
components and embedded solutions." - Wikipedia.org

Website: www.avnet.com
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/vendor-prefixes.txt

@@ -47,6 +47,7 @@ auvidea Auvidea GmbH
 avago	Avago Technologies
 avia	avia semiconductor
 avic	Shanghai AVIC Optoelectronics Co., Ltd.
+avnet	Avnet, Inc.
 axentia	Axentia Technologies AB
 axis	Axis Communications AB
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