thermal: msm8974: Fix calibration less temperature readings

The slope used for temperature calculation is code/degC.
Change the implementation of the equation of the line
to use the slope as code/degC instead of degC/code.

Update the control register default initialization data to
perform a periodic update of the temperature data to the
status registers.

Change-Id: Ia222e4ffa4009767a570a083910a37fd1823011c
Signed-off-by: Siddartha Mohanadoss <smohanad@codeaurora.org>