dt-bindings: add Plantower to the vendor prefixes

Add Plantower to the vendor prefixes.
Signed-off-by: NTomasz Duszynski <tduszyns@gmail.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Signed-off-by: NJonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/devicetree/bindings/vendor-prefixes.txt

@@ -304,6 +304,7 @@ phytec	PHYTEC Messtechnik GmbH
 picochip	Picochip Ltd
 pine64	Pine64
 pixcir  PIXCIR MICROELECTRONICS Co., Ltd
+plantower Plantower Co., Ltd
 plathome	Plat'Home Co., Ltd.
 plda	PLDA
 plx	Broadcom Corporation (formerly PLX Technology)