PM / runtime: Check ignore_children in pm_runtime_need_not_resume()

Modify pm_runtime_need_not_resume() to make it avoid taking
power.child_count for devices with power.ignore_children which
is consistent with the runtime PM usage of these fields.
Suggested-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/base/power/runtime.c

@@ -1616,7 +1616,8 @@ void pm_runtime_drop_link(struct device *dev)
 static bool pm_runtime_need_not_resume(struct device *dev)
 {
 	return atomic_read(&dev->power.usage_count) <= 1 &&
-		atomic_read(&dev->power.child_count) == 0;
+		(atomic_read(&dev->power.child_count) == 0 ||
+		 dev->power.ignore_children);
 }
 
 /**