sched: Adapt sched tracepoints for RV task model

Add the following tracepoint:
* sched_set_need_resched(tsk, cpu, tif)
    Called when a task is set the need resched [lazy] flag

Remove the unused ip parameter from sched_entry and sched_exit and alter
sched_entry to have a value of preempt consistent with the one used in
sched_switch.

Also adapt all monitors using sched_{entry,exit} to avoid breaking build.

These tracepoints are useful to describe the Linux task model and are
adapted from the patches by Daniel Bristot de Oliveira
(https://bristot.me/linux-task-model/).

Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Nam Cao <namcao@linutronix.de>
Cc: Tomas Glozar <tglozar@redhat.com>
Cc: Juri Lelli <jlelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Link: https://lore.kernel.org/20250728135022.255578-7-gmonaco@redhat.com


Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>