PM / Domains: Don't check for an existing device when adding a new

When adding a device to a genpd, we no longer need to walk genpd's list
of existing devices to verify it hasn't already been added.

Instead we can now rely on the verification of not allowing existing
generic_pm_domain_data for a device, since that has the same meaning.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/base/power/domain.c

@@ -1415,7 +1415,6 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
 			  struct gpd_timing_data *td)
 {
 	struct generic_pm_domain_data *gpd_data_new, *gpd_data = NULL;
-	struct pm_domain_data *pdd;
 	int ret = 0;
 
 	dev_dbg(dev, "%s()\n", __func__);
@@ -1434,12 +1433,6 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
 		goto out;
 	}
 
-	list_for_each_entry(pdd, &genpd->dev_list, list_node)
-		if (pdd->dev == dev) {
-			ret = -EINVAL;
-			goto out;
-		}
-
 	ret = dev_pm_get_subsys_data(dev);
 	if (ret)
 		goto out;