staging:ccg: fix a class_destroy when kmalloc fails after the class_create

we do class_create and call kmalloc to allocate dev pointer,
and if kmalloc fail we forget destoying class

Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/ccg/ccg.c

@@ -1254,8 +1254,10 @@ static int __init init(void)
 		return PTR_ERR(ccg_class);
 
 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
-	if (!dev)
+	if (!dev) {
+		class_destroy(ccg_class);
 		return -ENOMEM;
+	}
 
 	dev->functions = supported_functions;
 	INIT_LIST_HEAD(&dev->enabled_functions);