Update to the newest gnulib.

diff --git a/gnulib b/gnulib
index 3e75e00c40ff97b0b72a22c28e4bb9b8086602fb..9f00cc0d8c78cea9e427bb0c40d2ff50d86fe402 160000 (submodule)
--- a/gnulib
+++ b/gnulib
@@ -1 +1 @@
-Subproject commit 3e75e00c40ff97b0b72a22c28e4bb9b8086602fb
+Subproject commit 9f00cc0d8c78cea9e427bb0c40d2ff50d86fe402