soc: qcom: Add cpufreq limits voting mechanism to msm_perf module

Userspace might need to set scaling_min/scaling_max for different
usecases based on perf/power requirement.
Currently available userspace nodes exposed by cpufreq framework
might not be appropriate in situations where userspace wants to
revert back its vote and the CPU in question is offline. Add support
to msm_performance module to set min/max limits on cpufreq for
different CPUs such that the module maintains the userspace vote
across hotplugs and applies it whenever CPU policy gets updated
(after it comes online)

Change-Id: I1fab2a8b63d4ba13465ecd36adecddcb7c63b43a
Signed-off-by: Rohit Gupta <rohgup@codeaurora.org>
Signed-off-by: Pracheer <pracheer@codeaurora.org>