Thermal/int3403: Fix thermal hysteresis unit conversion

Thermal hysteresis represents a temperature difference.
But the original code treats it as a temperature value,
Convert it from tenths of degree Kelvin to Milli-Celsius
by deducing 273200. This is not right.

Kelvin and Celsius have same degree size. From temperature
difference view, the conversion between tenths of degree
Kelvin unit and Milli-Celsius unit is just to multiply 100.

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>