class: Free the class private data in class_release

Fix a memory leak by freeing the memory allocated in __class_register
for the class private data.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/base/class.c

@@ -59,6 +59,8 @@ static void class_release(struct kobject *kobj)
 	else
 		pr_debug("class '%s' does not have a release() function, "
 			 "be careful\n", class->name);
+
+	kfree(cp);
 }
 
 static struct sysfs_ops class_sysfs_ops = {