iio: adc: add imx93 adc support

The ADC in i.mx93 is a total new ADC IP, add a driver to support
this ADC.

Currently, only support one shot normal conversion triggered by
software. For other mode, will add in future.

Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Link: https://lore.kernel.org/r/20230117135137.1735536-2-haibo.chen@nxp.com


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