of: Add vendor prefix for Linear Technology Corporation

Add Linear Technology Corporation to the list of device tree vendor prefixes.
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NMark Brown <broonie@linaro.org>

Documentation/devicetree/bindings/vendor-prefixes.txt

@@ -65,6 +65,7 @@ lantiq	Lantiq Semiconductor
 lg	LG Corporation
 linux	Linux-specific binding
 lsi	LSI Corp. (LSI Logic)
+lltc	Linear Technology Corporation
 marvell	Marvell Technology Group Ltd.
 maxim	Maxim Integrated Products
 microchip	Microchip Technology Inc.