PM / Domains: Don't kfree() the virtual device in the error path

It's not correct to call kfree(dev) when device_register(dev) has failed.

Fix this by calling put_device(dev) instead.

Fixes: 3c095f32a9 ("PM / Domains: Add support for multi PM domains per device to genpd")
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Niklas Cassel <niklas.cassel@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/base/power/domain.c

@@ -2455,7 +2455,7 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev,
 
 	ret = device_register(virt_dev);
 	if (ret) {
-		kfree(virt_dev);
+		put_device(virt_dev);
 		return ERR_PTR(ret);
 	}