If `log updates` is set and state.nexthop is null, addr2sa() is not happy and
crashes the daemon.
Check if state.nexthop is NULL before passing state.nexthop->exit_nexthop (as
done in network_add())

Index: rde.c
===================================================================
RCS file: /cvs/src/usr.sbin/bgpd/rde.c,v
diff -u -p -r1.646 rde.c
--- rde.c	12 Dec 2024 20:19:03 -0000	1.646
+++ rde.c	3 Jan 2025 17:03:35 -0000
@@ -1895,8 +1895,8 @@ rde_update_update(struct rde_peer *peer,
 
 		if (action == ACTION_ALLOW) {
 			rde_update_log("update", i, peer,
-			    &state.nexthop->exit_nexthop, prefix,
-			    prefixlen);
+			    state.nexthop ? &state.nexthop->exit_nexthop : NULL,
+			    prefix, prefixlen);
 			prefix_update(rib, peer, path_id, path_id_tx, &state,
 			    0, prefix, prefixlen);
 		} else if (conf->filtered_in_locrib && i == RIB_LOC_START) {