Update to the newest gnulib.

diff --git a/gnulib b/gnulib
index 1ddf50761d5c485e2f509ea935379886d50c245f..979dcc75b404ed579e588e048a13145f04440e15 160000 (submodule)
--- a/gnulib
+++ b/gnulib
@@ -1 +1 @@
-Subproject commit 1ddf50761d5c485e2f509ea935379886d50c245f
+Subproject commit 979dcc75b404ed579e588e048a13145f04440e15