ACPI: processor: idle: Fix memory leak when register cpuidle device failed

The cpuidle device's memory is leaked when cpuidle device registration
fails in acpi_processor_power_init().  Free it as appropriate.

Fixes: 3d339dc ("cpuidle / ACPI : move cpuidle_device field out of the acpi_processor_power structure")
Signed-off-by: Huisong Li <lihuisong@huawei.com>
Link: https://patch.msgid.link/20250728070612.1260859-2-lihuisong@huawei.com
[ rjw: Changed the order of the new statements, added empty line after if () ]
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Author: LiHuiSong1

drivers/acpi/processor_idle.c

@@ -1405,6 +1405,9 @@ int acpi_processor_power_init(struct acpi_processor *pr)
 		if (retval) {
 			if (acpi_processor_registered == 0)
 				cpuidle_unregister_driver(&acpi_idle_driver);
+
+			per_cpu(acpi_cpuidle_device, pr->id) = NULL;
+			kfree(dev);
 			return retval;
 		}
 		acpi_processor_registered++;