dts: binding: sensor: stm32-temp add temp sensor calibration property

The TS_CAL values for the temperature sensor are measured on 12, 14 and
16 bit resolution depends on the STM32 series. Because the drivers
operates at 12 bit resolution the TS_CAL1 and TS_CAL2 must be divided.

Signed-off-by: TLIG Dhaou <dhaou.tlig-ext@st.com>