Update to the newest gnulib.

diff --git a/gnulib b/gnulib
index 0003b01876cb929ab10ac4fe409db20d6e4c1f0e..7397561e64f9b96a4a1638117ce18d06133a60f1 160000 (submodule)
--- a/gnulib
+++ b/gnulib
@@ -1 +1 @@
-Subproject commit 0003b01876cb929ab10ac4fe409db20d6e4c1f0e
+Subproject commit 7397561e64f9b96a4a1638117ce18d06133a60f1