route: add missing rtnl_nh_* symbols

When nh support was added in 780d06a ("route: add nh type"),
several functions were missed when adding the symbols to
libnl-route-3.sym.

Add the missing symbols so they can actually get used.

Fixes: 780d06a ("route: add nh type")
Signed-off-by: Jonas Gorski <[email protected]>

Author: KanjiMonster

libnl-route-3.sym

@@ -1296,12 +1296,15 @@ global:
 	rtnl_neigh_set_nhid;
 	rtnl_nh_alloc;
 	rtnl_nh_alloc_cache;
+	rtnl_nh_clone;
+	rtnl_nh_dump;
 	rtnl_nh_get;
 	rtnl_nh_get_fdb;
 	rtnl_nh_get_gateway;
 	rtnl_nh_get_group_entry;
 	rtnl_nh_get_group_size;
 	rtnl_nh_get_id;
+	rtnl_nh_get_oif;
 	rtnl_nh_put;
 	rtnl_nh_set_fdb;
 	rtnl_nh_set_gateway;