iio: adc: hx711: Add DT binding for avia,hx711

Add DT bindings for avia,hx711
Add vendor avia to vendor list
Signed-off-by: Andreas Klinger <ak@it-klinger.de>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Documentation/devicetree/bindings/iio/adc/avia-hx711.txt

+* AVIA HX711 ADC chip for weight cells
+  Bit-banging driver
+
+Required properties:
+ - compatible:	Should be "avia,hx711"
+ - sck-gpios:	Definition of the GPIO for the clock
+ - dout-gpios:	Definition of the GPIO for data-out
+		See Documentation/devicetree/bindings/gpio/gpio.txt
+ - avdd-supply:	Definition of the regulator used as analog supply
+
+Example:
+weight@0 {
+	compatible = "avia,hx711";
+	sck-gpios = <&gpio3 10 GPIO_ACTIVE_HIGH>;
+	dout-gpios = <&gpio0 7 GPIO_ACTIVE_HIGH>;
+	avdd-suppy = <&avdd>;
+};
+

Documentation/devicetree/bindings/vendor-prefixes.txt

@@ -38,6 +38,7 @@ atmel	Atmel Corporation
 auo	AU Optronics Corporation
 auvidea Auvidea GmbH
 avago	Avago Technologies
+avia	avia semiconductor
 avic	Shanghai AVIC Optoelectronics Co., Ltd.
 axentia	Axentia Technologies AB
 axis	Axis Communications AB