intel_idle: Fix dangling registration on error path.

In the module_init() method, if the per-CPU allocation fails, then the
active cpuidle registration is not cleaned up.  This patch fixes the
issue by attempting the allocation before registration, and then
cleaning it up again on registration failure.

Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index 4a1de3d..5dd741f 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -1210,19 +1210,20 @@
 	if (retval)
 		return retval;
 
+	intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device);
+	if (intel_idle_cpuidle_devices == NULL)
+		return -ENOMEM;
+
 	intel_idle_cpuidle_driver_init();
 	retval = cpuidle_register_driver(&intel_idle_driver);
 	if (retval) {
 		struct cpuidle_driver *drv = cpuidle_get_driver();
 		printk(KERN_DEBUG PREFIX "intel_idle yielding to %s",
 			drv ? drv->name : "none");
+		free_percpu(intel_idle_cpuidle_devices);
 		return retval;
 	}
 
-	intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device);
-	if (intel_idle_cpuidle_devices == NULL)
-		return -ENOMEM;
-
 	cpu_notifier_register_begin();
 
 	for_each_online_cpu(i) {