of: add vendor prefix for PHYTEC Messtechnik GmbH

Adds PHYTEC to the list of DT vendor prefixes.
Signed-off-by: Matt Porter <matt.porter@linaro.org>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>

Documentation/devicetree/bindings/vendor-prefixes.txt

@@ -46,6 +46,7 @@ nintendo	Nintendo
 nvidia	NVIDIA
 nxp	NXP Semiconductors
 onnn	ON Semiconductor Corp.
+phytec	PHYTEC Messtechnik GmbH
 picochip	Picochip Ltd
 powervr	PowerVR (deprecated, use img)
 qca	Qualcomm Atheros, Inc.