hwmon: (pmbus/max20830) add driver for max20830

hwmon: (pmbus/max20830) add driver for max20830

Add support for MAX20830 step-down DC-DC switching regulator with
PMBus interface. It allows monitoring of input/output voltage,
output current and temperature through the PMBus serial interface.

Signed-off-by: Alexis Czezar Torreno <alexisczezar.torreno@analog.com>
Link: https://lore.kernel.org/r/20260505-dev_max20830-v4-2-4343dcbfd7d7@analog.com
[groeck: checkpatch cleanup (space before and after '-')]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>