[SCSI] fc class: fix fc_transport_init error handling

If transport_class_register fails we should unregister any
registered classes, or we will leak memory or other
resources.

I did a quick modprobe of scsi_transport_fc to test the
patch.
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

drivers/scsi/scsi_transport_fc.c

@@ -649,11 +649,22 @@ static __init int fc_transport_init(void)
 		return error;
 	error = transport_class_register(&fc_vport_class);
 	if (error)
-		return error;
+		goto unreg_host_class;
 	error = transport_class_register(&fc_rport_class);
 	if (error)
-		return error;
-	return transport_class_register(&fc_transport_class);
+		goto unreg_vport_class;
+	error = transport_class_register(&fc_transport_class);
+	if (error)
+		goto unreg_rport_class;
+	return 0;
+
+unreg_rport_class:
+	transport_class_unregister(&fc_rport_class);
+unreg_vport_class:
+	transport_class_unregister(&fc_vport_class);
+unreg_host_class:
+	transport_class_unregister(&fc_host_class);
+	return error;
 }
 
 static void __exit fc_transport_exit(void)