ANDROID: sched/tune: Move SchedTune cpu API into UtilClamp wrappers

The a SchedTune CPU boosting API is currently used from sugov_get_util()
to get the boosted utilization and to pass it into schedutil_freq_util().
When UtilClamp is in use instead we call schedutil_freq_util() by
passing in just the aggregated CFS+RT utilization and the clamping is
done internally only on FREQUENCY_UTIL calls.

This asymmetry is not required moreover, schedutil code is polluted by
non-mainline SchedTune code.

Wrap SchedTune API call related to cpu utilization boosting with a more
generic and mainlinish UtilClamp call:

 - uclamp_util(cpu, util)  <= boosted_cpu_util(cpu)

This new API is already used in schedutil_freq_util() to clamp the
aggregated RT+CFS utilization on FREQUENCY_UTIL calls.

Move the cpu boosting into uclamp_util so that we remove any SchedTune
specific bit from kernel/sched/cpufreq_schedutil.c.

Get rid of the no more required boosted_cpu_util(cpu) method and replace
it with a stune_util(cpu, util) which signature is better aligned with
its uclamp_util(cpu, util) wrapping method.

Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
[
 Since we are at that, fix compilation warning due to capacity_orig_of()
 being "defined by not used" generated by rt and deadline compilation
 units.
]
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
Signed-off-by: Qais Yousef <qais.yousef@arm.com>