iio:proximity:sx9324: Add dt_binding support

Based on bindings/iio/proximity/semtech,sx9324.yaml, implement
retrieving sensor hardware property and alter default values.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20220101203817.290512-6-gwendal@chromium.org


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