Update gnulib.

diff --git a/gnulib b/gnulib
index efc854066a28129c347be9f8226b43919c8f5a74..8f6c54d191839962d35c99c9bb537a302aab5717 160000 (submodule)
--- a/gnulib
+++ b/gnulib
@@ -1 +1 @@
-Subproject commit efc854066a28129c347be9f8226b43919c8f5a74
+Subproject commit 8f6c54d191839962d35c99c9bb537a302aab5717