If lm80_read_value() fails, it returns a negative number instead of the
correct read data. Therefore, we should avoid using the data if it
fails.
The fix checks if lm80_read_value() fails, and if so, returns with the
error number.
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
[groeck: One variable for return values is enough]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
