net: netdev_kobject_init: annotate with __init

netdev_kobject_init() is only being called from __init context,
that is, net_dev_init(), so annotate it with __init as well, thus
the kernel can take this as a hint that the function is used only
during the initialization phase and free up used memory resources
after its invocation.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/core/net-sysfs.c

@@ -1358,7 +1358,7 @@ void netdev_class_remove_file_ns(struct class_attribute *class_attr,
 }
 EXPORT_SYMBOL(netdev_class_remove_file_ns);
 
-int netdev_kobject_init(void)
+int __init netdev_kobject_init(void)
 {
 	kobj_ns_type_register(&net_ns_type_operations);
 	return class_register(&net_class);

net/core/net-sysfs.h

 #ifndef __NET_SYSFS_H__
 #define __NET_SYSFS_H__
 
-int netdev_kobject_init(void);
+int __init netdev_kobject_init(void);
 int netdev_register_kobject(struct net_device *);
 void netdev_unregister_kobject(struct net_device *);
 int net_rx_queue_update_kobjects(struct net_device *, int old_num, int new_num);