[core/sched/cbs] Shrink round_rt_correction name

This is just a dummy patch to use a shorted name for the round correction
RQ status variable.

Signed-off-by: Patrick Bellasi <derkling@gmail.com>
[core/sched/cbs] Report RQ round correction old via FTrace

This patch allows to trace the round correction old value which is the
actual round correction control value, which is necessary to validate
the controller behavior.

Signed-off-by: Patrick Bellasi <derkling@gmail.com>
[cores/sched/cbs] Reset Burst Error on reinitialization

This reset allows to properly trace the last computed error on each
Burst event.

Signed-off-by: Patrick Bellasi <derkling@gmail.com>
[core/sched/cbs] Update burst FTrace event

This patch adds tracing of burst error and next value, to support a more
complete tracing of control status.
Moreover, all "burts" related events are not labelled with "Tb_" prefix.

Signed-off-by: Patrick Bellasi <derkling@gmail.com>
[core/sched/cbs] Keep count of Burst Preemption and Yields

These two counters allows to distinguish how many burst are voluntary
preemption or HRTimer forced. This should allows to better verify both
the HRTimer working as well as the workload behaviors.
The number of voluntary CPU yields is counted as well.

Signed-off-by: Patrick Bellasi <derkling@gmail.com>