Update to the newest gnulib.

diff --git a/gnulib b/gnulib
index 1480501f4f8d47a8eea203c5b180262888e28bba..6ebad7abf8bccb2c63e8b13fc0be81216c3b0cc3 160000 (submodule)
--- a/gnulib
+++ b/gnulib
@@ -1 +1 @@
-Subproject commit 1480501f4f8d47a8eea203c5b180262888e28bba
+Subproject commit 6ebad7abf8bccb2c63e8b13fc0be81216c3b0cc3