sched/uclamp: feec(): Take uclamp into account in early exit condition

If the utilization of the woken up task is 0, we skip the energy
calculation because it has no impact.

But if the task is boosted (uclamp_min != 0) will have an impact on task
placement and frequency selection. Only skip if the util is truly
0 after applying uclamp values.

Change uclamp_task_cpu() signature to avoid unnecessary additional calls
to uclamp_eff_get(). feec() is the only user now.

Fixes: 732cd75b ("sched/fair: Select an energy-efficient CPU on task wake-up")
Signed-off-by: Qais Yousef <qais.yousef@arm.com>