[PATCH] build: update to latest gnulib

[Pádraig Brady]

Pick up recent build fixes to avoid sysctl.h inclusion on glibc systems,
and to restrict the max file size supported by read-file to PTRDIFF_MAX.
---
 gnulib | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gnulib b/gnulib
index 7d0693789..bf718ebcb 160000
--- a/gnulib
+++ b/gnulib
@@ -1 +1 @@
-Subproject commit 7d069378921bfa0d7c7198ea177aac0a2440016f
+Subproject commit bf718ebcb3ba3b12871eb293f49d80915cc05b0c
-- 
2.24.1