cksum,wc: inspect GLIBC_TUNABLES on all architectures

* gnulib: Update gnulib to latest to pull in change
to inspect GLIBC_TUNABLES on non x86_64 or aarch64 platforms.
This was needed on 32 bit x86, which supports calling into
accelerated code, and so requires inspection of GLIBC_TUNABLES
to pass the disablement verification in tests/cksum/cksum.sh

diff --git a/gnulib b/gnulib
index 6b7a999681243e3aed9089a7697cf51119de04b1..395bd7a734a1c0beb4daa25130c4a1cdfad5719d 160000 (submodule)
--- a/gnulib
+++ b/gnulib
@@ -1 +1 @@
-Subproject commit 6b7a999681243e3aed9089a7697cf51119de04b1
+Subproject commit 395bd7a734a1c0beb4daa25130c4a1cdfad5719d