dt-bindings: iio: afe: current-sense-amplifier: Add io-channel-cells

The current-sense-amplifier is an IIO provider thus can be referenced by
IIO consumers (via "io-channels" property in consumer device node). Such
provider is required to describe number of cells used in phandle lookup
with "io-channel-cells" property.

Signed-off-by: Primoz Fiser <primoz.fiser@norik.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20250905065503.3022107-1-primoz.fiser@norik.com


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