cpufreq: cpufreq_register_driver() should return -ENODEV if init fails

commit 6c770036 upstream.

For a driver that does not set the CPUFREQ_STICKY flag, if all of the
->init() calls fail, cpufreq_register_driver() should return an error.
This will prevent the driver from loading.

Fixes: ce1bcfe9 (cpufreq: check cpufreq_policy_list instead of scanning policies for all CPUs)
Signed-off-by: David Arcari <darcari@redhat.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/cpufreq/cpufreq.c

@@ -2451,6 +2451,7 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
 	if (!(cpufreq_driver->flags & CPUFREQ_STICKY) &&
 	    list_empty(&cpufreq_policy_list)) {
 		/* if all ->init() calls failed, unregister */
+		ret = -ENODEV;
 		pr_debug("%s: No CPU initialized for driver %s\n", __func__,
 			 driver_data->name);
 		goto err_if_unreg;