Update to newest gnulib.

diff --git a/gnulib b/gnulib
index 1da6756b47bf931bbcc6756d16ae0f144f552bbb..b2b037e380eda6aef711ea5f625e26fb4a663c6e 160000 (submodule)
--- a/gnulib
+++ b/gnulib
@@ -1 +1 @@
-Subproject commit 1da6756b47bf931bbcc6756d16ae0f144f552bbb
+Subproject commit b2b037e380eda6aef711ea5f625e26fb4a663c6e