msm: thermal: Initialize per cpu variables during thermal init

Initializing the per cpu variables inside frequency/hotplug
probe function has a possibility that it may result in
uninitialized variables. So initialize the per cpu variables
in the thermal drivers init function.

Change-Id: Id01666d1ddf6de1a1078d6900d8bb86b77adbf56
Signed-off-by: Ram Chandrasekar <rkumbako@codeaurora.org>