PM: sleep: s2idle: Replace deprecated CPU-hotplug functions

The functions get_online_cpus() and put_online_cpus() have been
deprecated during the CPU hotplug rework. They map directly to
cpus_read_lock() and cpus_read_unlock().

Replace deprecated CPU-hotplug functions with the official version.
The behavior remains unchanged.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

kernel/power/suspend.c

@@ -96,7 +96,7 @@ static void s2idle_enter(void)
 	s2idle_state = S2IDLE_STATE_ENTER;
 	raw_spin_unlock_irq(&s2idle_lock);
 
-	get_online_cpus();
+	cpus_read_lock();
 	cpuidle_resume();
 
 	/* Push all the CPUs into the idle loop. */
@@ -106,7 +106,7 @@ static void s2idle_enter(void)
 		    s2idle_state == S2IDLE_STATE_WAKE);
 
 	cpuidle_pause();
-	put_online_cpus();
+	cpus_read_unlock();
 
 	raw_spin_lock_irq(&s2idle_lock);