ARM: dts: msm: Enable fcc stepping for sm6150

FCC stepping logic gradually ramps up/down the FCC whenever there
is a change in its value, distributing the thermal delta over time.
This prevents a sudden increase/decrease in FCC which can impact
the PMIC die thermally causing XO to drift.

Enable FCC stepping algorithm for sm6150 target.

Change-Id: I5229d4e54f64b64ed4477547ea4be6e6421c67db
Signed-off-by: Umang Agrawal <uagrawal@codeaurora.org>