build: update gnulib, to fix OpenBSD test failures

diff --git a/gnulib b/gnulib
index 9e43bb61e60a318da34628989e8a754aee18a285..a1885e2dc2a8f1c79ead4e6ceca1a53827b89048 160000 (submodule)
--- a/gnulib
+++ b/gnulib
@@ -1 +1 @@
-Subproject commit 9e43bb61e60a318da34628989e8a754aee18a285
+Subproject commit a1885e2dc2a8f1c79ead4e6ceca1a53827b89048