ACPI / bus: handle ACPI hotplug schedule errors completely

Kernel should decrements the reference count of ACPI device
when the scheduling of ACPI hotplug work failed, and evaluates
_OST to notify BIOS the failure.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: "Lee, Chun-Yi" <jlee@suse.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 784bda6..9d4fea6 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -432,11 +432,15 @@
 	    (driver->flags & ACPI_DRIVER_ALL_NOTIFY_EVENTS))
 		driver->ops.notify(adev, type);
 
-	if (hotplug_event && ACPI_SUCCESS(acpi_hotplug_schedule(adev, type)))
+	if (!hotplug_event) {
+		acpi_bus_put_acpi_device(adev);
+		return;
+	}
+
+	if (ACPI_SUCCESS(acpi_hotplug_schedule(adev, type)))
 		return;
 
 	acpi_bus_put_acpi_device(adev);
-	return;
 
  err:
 	acpi_evaluate_ost(handle, type, ost_code, NULL);