hwmon: (pmbus/zl6100) Add support for ZLS1003, ZLS4009 and ZL8802

Add support for Renesas ZL8802 Dual Channel/Dual Phase PMBus DC/DC
Digital Controller as well as ZLS1003 and ZLS4009 custom DC/DC
controller chips.

Signed-off-by: Erik Rosen <erik.rosen@metormote.com>
Link: https://lore.kernel.org/r/20210423153329.33457-2-erik.rosen@metormote.com


Signed-off-by: Guenter Roeck <linux@roeck-us.net>