of: Add vendor prefix for QiaoDian Xianshi

Use "qiaodian" as the vendor prefix for QiaoDian Xianshi Corporation in
device tree compatible strings.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>

Documentation/devicetree/bindings/vendor-prefixes.txt

@@ -182,6 +182,7 @@ qca	Qualcomm Atheros, Inc.
 qcom	Qualcomm Technologies, Inc
 qemu	QEMU, a generic and open source machine emulator and virtualizer
 qi	Qi Hardware
+qiaodian	QiaoDian XianShi Corporation
 qnap	QNAP Systems, Inc.
 radxa	Radxa
 raidsonic	RaidSonic Technology GmbH