sched: add frequency zone awareness to the load balancer

Add zone awareness to the load balancer. Remove all earlier restrictions
that the load balancer had for inter cluster kicks and migration.

Change-Id: I12ad3d0c2d2e9bb498f49a231810f2ad418b061f
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>