iio: adc: ad4030: add support for ad4632-16 and ad4632-24

iio: adc: ad4030: add support for ad4632-16 and ad4632-24

AD4632-24 and AD4632-16 are 2 channels ADCs. Both channels are
interleaved bit per bit on SDO line.

Both of them do not have evaluation board. As such, the support added
here can't be tested. Support is provided as best effort until someone get
their hands on one.

Signed-off-by: Esteban Blanc <eblanc@baylibre.com>
Link: https://patch.msgid.link/20250214-eblanc-ad4630_v1-v4-5-135dd66cab6a@baylibre.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>