netlink: remove unused exports

I added those myself in commits b4ff4f04 and 84659eb5,
but I see no reason now why they should be exported,
only generic netlink uses them which cannot be modular.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/netlink/af_netlink.c

@@ -1541,7 +1541,6 @@ int netlink_change_ngroups(struct sock *sk, unsigned int groups)
 	kfree(old);
 	return err;
 }
-EXPORT_SYMBOL(netlink_change_ngroups);
 
 /**
  * netlink_clear_multicast_users - kick off multicast listeners
@@ -1564,7 +1563,6 @@ void netlink_clear_multicast_users(struct sock *ksk, unsigned int group)
 
 	netlink_table_ungrab();
 }
-EXPORT_SYMBOL(netlink_clear_multicast_users);
 
 void netlink_set_nonroot(int protocol, unsigned int flags)
 {