hwmon: (pmbus/tda38640) Add driver for Infineon TDA38640 Voltage Regulator

Add the pmbus driver for the Infineon TDA38640 voltage regulator.

Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
Link: https://lore.kernel.org/r/20230124202317.3704963-2-Naresh.Solanki@9elements.com


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