sched: Add deadline tracepoints

sched: Add deadline tracepoints

Add the following tracepoints:

* sched_dl_throttle(dl_se, cpu, type):
    Called when a deadline entity is throttled
* sched_dl_replenish(dl_se, cpu, type):
    Called when a deadline entity's runtime is replenished
* sched_dl_update(dl_se, cpu, type):
    Called when a deadline entity updates without throttle or replenish
* sched_dl_server_start(dl_se, cpu, type):
    Called when a deadline server is started
* sched_dl_server_stop(dl_se, cpu, type):
    Called when a deadline server is stopped

Those tracepoints can be useful to validate the deadline scheduler with
RV and are not exported to tracefs.

Reviewed-by: Phil Auld <pauld@redhat.com>
Acked-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lore.kernel.org/r/20260330111010.153663-11-gmonaco@redhat.com
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>