Dietmar Eggemann authored Jun 23, 2014 and Morten Rasmussen committed Jul 21, 2014

Attempt to pick the source cpu which potentially gives the maximum energy
savings in case the minimum of the amount of utilization which the
destination cpu is additionally able to handle and the current
utilization on the source cpu is taken away from it and put on the
destination cpu instead.
Finding the optimum source requires an exhaustive search through all cpus
in the groups. Instead, the source group is determined based on
utilization and probing the energy cost on a single cpu in each group.

This implementation is not providing an actual energy aware load
balancing right now. It is only trying to showcase the way to find the
most suitable source queue (cpu) based on the energy aware data. The
actual load balance is still done based on the calculated load based
imbalance.

Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>