ANDROID: sched: use util instead of capacity to select busy cpu

If cpus are busy, the cpu selection algorithm was favoring
cpus with lower capacity. This can result in uneven packing
since there will be a bias toward the same cpu until there
is a capacity change. Instead use the utilization so there
is immediate feedback as tasks are assigned

BUG: 30115868

Change-Id: I0ac7ae3ab5d8f2f5a5838c29bb6da2c3e8ef44e8
Signed-off-by: Andres Oportus <andresoportus@google.com>