dt-bindings: iio: adi,ad7923: add adi,range-double property

Document the new property to enable doubling the analog input range.
Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220912081223.173584-4-nuno.sa@analog.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Documentation/devicetree/bindings/iio/adc/adi,ad7923.yaml

@@ -36,6 +36,10 @@ properties:
     description: |
       The regulator supply for ADC reference voltage.
 
+  adi,range-double:
+    description: Sets the analog input range from 0 to 2xVREF.
+    type: boolean
+
   '#address-cells':
     const: 1