dt-bindings: iio: adc: ad4130: use spi-peripheral-props.yaml

Reference the "spi-peripheral-props.yaml" schema to allow using
all SPI device properties.

Signed-off-by: Cosmin Tanislav <cosmin.tanislav@analog.com>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20221115151955.394030-1-cosmin.tanislav@analog.com


Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>