Allow temperature calibration

Add a field in CMOS and in configuration page to set a ΔT (say from -5 to +5°C) that will be automatically added to the output temperature.

Technically, ΔT is stored as an integer between -50 and 50 and is expressed in tenth of °C.

• Add configuration field in CMOS
• Update CMOS structure for migration
• Use value in CMOS to compute new temperature