cpufreq: Explain the kobject_put() in cpufreq_policy_alloc()

It may not be particularly clear why the kobject_put() after
failing kobject_init_and_add() in cpufreq_policy_alloc() is not
redundant, so add a comment to explain that.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

drivers/cpufreq/cpufreq.c

@@ -1134,6 +1134,11 @@ static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu)
 				   cpufreq_global_kobject, "policy%u", cpu);
 	if (ret) {
 		pr_err("%s: failed to init policy->kobj: %d\n", __func__, ret);
+		/*
+		 * The entire policy object will be freed below, but the extra
+		 * memory allocated for the kobject name needs to be freed by
+		 * releasing the kobject.
+		 */
 		kobject_put(&policy->kobj);
 		goto err_free_real_cpus;
 	}