hwmon: (w83627ehf) Add support for suspend

On suspend some register values are lost, most notably the Value RAM
areas but also other limits and settings. Restore them on resume.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>