cpuidle: psci: Activate GENPD_FLAG_ACTIVE_WAKEUP with OSI

Set GENPD_FLAG_ACTIVE_WAKEUP flag for domain psci cpuidle when OSI
is activated, then when a device is set as the wake-up source using
device_set_wakeup_path, the PSCI power domain could be retained to allow
so that the associated device can wake up the system.

With this flag, for S2IDLE system-wide suspend, the wake-up path is
managed in each device driver and is tested in the power framework:
a PSCI domain is only turned off when GENPD_FLAG_ACTIVE_WAKEUP is enabled
and the associated device is not in the wake-up path, so PSCI CPUIdle
selects the lowest level in the PSCI topology according to the wake-up
path.

This patch is a preliminary step to support PSCI OSI on the STM32MP25
platform with the D1 domain (power-domain-cluster) for the A35 cortex
cluster and for the associated peripherals including EXTI1 which manages
the wake-up interrupts for domain D1.

Signed-off-by: Patrick Delaunay <[e-mail]>
Message-ID: <20241119141827.1.I6129b16ec6b558efc1707861db87e55bf7022f62@changeid>
Signed-off-by: Ulf Hansson <[e-mail]>

drivers/cpuidle/cpuidle-psci-domain.c

···
 	 */
 	if (use_osi) {
 		pd->power_off = psci_pd_power_off;
+		pd->flags |= GENPD_FLAG_ACTIVE_WAKEUP;
 		if (IS_ENABLED(CONFIG_PREEMPT_RT))
 			pd->flags |= GENPD_FLAG_RPM_ALWAYS_ON;
 	} else {