hwmon: (lm92) Replace chip IDs with limit register resolution

The chip IDs are not used by the driver. Drop them. Use driver data to
store the limit register resolution instead, and use this information
when writing temperature limits to improve chip specific rounding and
to avoid writing into unused register bits.

Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>