thermal/drivers/tsens: Support using nvmem cells for calibration data

Add a unified function using nvmem cells for parsing the calibration
data rather than parsing the calibration blob manually.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20230101194034.831222-10-dmitry.baryshkov@linaro.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>