Update rdns.

diff --git a/src/rdns b/src/rdns
index 429e2100724fa709e64011951edee8d1e747d04e..8d80ac78cf6436c077804dd0972866a5bd55732f 160000 (submodule)
--- a/src/rdns
+++ b/src/rdns
@@ -1 +1 @@
-Subproject commit 429e2100724fa709e64011951edee8d1e747d04e
+Subproject commit 8d80ac78cf6436c077804dd0972866a5bd55732f