build: update gnulib submodule to latest

diff --git a/gnulib b/gnulib
index 0e8fd2c0eed44dba1d39840a8733c9159220d671..d57daa5979535178a57789403506270b6311cc85 160000 (submodule)
--- a/gnulib
+++ b/gnulib
@@ -1 +1 @@
-Subproject commit 0e8fd2c0eed44dba1d39840a8733c9159220d671
+Subproject commit d57daa5979535178a57789403506270b6311cc85