hwmon: (max6697) Fix swapped temp{1,8} critical alarms

The critical alarm bit for the local temperature sensor (temp1) is in
bit 7 of register 0x45 (not bit 6), and the critical alarm bit for remote
temperature sensor 7 (temp8) is in bit 6 (not bit 7).

This only affects MAX6581 since all other chips supported by this driver
do not support those critical alarms.

Fixes: 5372d2d7 ("hwmon: Driver for Maxim MAX6697 and compatibles")
Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>