hwmon: (w83627hf) Don't touch nonexistent I2C address registers

Only the W83627HF could be accessed through I2C. All other supported
chips are LPC-only, so they do not have I2C address registers. Don't
write to nonexistent or reserved registers on these chips.

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