thermal: msm8974-tsens: Modify calibration routine

Modify calibration routine to support variable number of
sensors. This is to have a single routine that can be
used to support multiple platforms provided similar
calibration masks are also used across multiple platforms.

Change-Id: I62bcca1bbe1175091f8dd7ca0997107b30cb9051
Signed-off-by: Siddartha Mohanadoss <smohanad@codeaurora.org>