gtp-rtnl: real_ifname is not long needed, remove it

Signed-off-by: Andreas Schultz <aschultz@tpip.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/src/gtp-rtnl.c b/src/gtp-rtnl.c
index 76e2021..527015b 100644
--- a/src/gtp-rtnl.c
+++ b/src/gtp-rtnl.c
@@ -104,8 +104,7 @@
 	return ret;
 }
 
-int gtp_dev_create(int dest_ns, const char *gtp_ifname, const char *real_ifname,
-		   int fd0, int fd1)
+int gtp_dev_create(int dest_ns, const char *gtp_ifname, int fd0, int fd1)
 {
 	char buf[MNL_SOCKET_BUFFER_SIZE];
 	struct nlmsghdr *nlh;
@@ -122,7 +121,6 @@
 
 	if (dest_ns >= 0)
 		mnl_attr_put_u32(nlh, IFLA_NET_NS_FD, dest_ns);
-	mnl_attr_put_u32(nlh, IFLA_LINK, if_nametoindex(real_ifname));
 	mnl_attr_put_str(nlh, IFLA_IFNAME, gtp_ifname);
 	nest = mnl_attr_nest_start(nlh, IFLA_LINKINFO);
 	mnl_attr_put_str(nlh, IFLA_INFO_KIND, "gtp");