Update gnulib.

diff --git a/gnulib b/gnulib
index ade95dda0df7e42c80c5e6d7cb51fe44d0663719..efc854066a28129c347be9f8226b43919c8f5a74 160000 (submodule)
--- a/gnulib
+++ b/gnulib
@@ -1 +1 @@
-Subproject commit ade95dda0df7e42c80c5e6d7cb51fe44d0663719
+Subproject commit efc854066a28129c347be9f8226b43919c8f5a74