msm: thermal: Add support to get cluster frequency plan in KTM

Add support in KTM to get the frequency plan of different
clusters and store them locally.

Removed a redundant function in KTM, which also
does the similar functionality.

Change-Id: I64cafd0a48ebc6905b3790a4421cbda8cf059196
Signed-off-by: Ram Chandrasekar <rkumbako@codeaurora.org>