hwmon: Add Ampere's Altra smpro-hwmon driver

This commit adds support for Ampere SMpro hwmon driver. This driver
supports accessing various CPU sensors provided by the SMpro co-processor
including temperature, power, voltages, and current.

Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com>
Link: https://lore.kernel.org/r/20220929094321.770125-2-quan@os.amperecomputing.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>