ieee802154: add __init to lowpan_frags_sysctl_register

lowpan_frags_sysctl_register is only called by __init lowpan_net_frag_init
(part of the lowpan module).
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ieee802154/reassembly.c

@@ -485,7 +485,7 @@ static void __net_exit lowpan_frags_ns_sysctl_unregister(struct net *net)
 
 static struct ctl_table_header *lowpan_ctl_header;
 
-static int lowpan_frags_sysctl_register(void)
+static int __init lowpan_frags_sysctl_register(void)
 {
 	lowpan_ctl_header = register_net_sysctl(&init_net,
 						"net/ieee802154/6lowpan",
@@ -498,7 +498,7 @@ static void lowpan_frags_sysctl_unregister(void)
 	unregister_net_sysctl_table(lowpan_ctl_header);
 }
 #else
-static inline int lowpan_frags_ns_sysctl_register(struct net *net)
+static inline int __init lowpan_frags_ns_sysctl_register(struct net *net)
 {
 	return 0;
 }