1. Temp detection has been gated behind of `--*-temp`. Don't make it a slow operation
2. According to [the kernel doc](https://www.kernel.org/doc/Documentation/hwmon/sysfs-interface), `temp1_input` is millidegree Celsius, which should be divided by 1000
3. There is no `/sys/class/hwmon/hwmon3/device/class` on my laptop, but `/sys/class/hwmon/hwmon3/device/device/class`. Need to confirm with @LinusDierheimer
4. Small code optimizations