sysdeps/gnu/configure.ac: handle correctly $libc_cv_rootsbindir

Upstream-Status:Pending
Signed-off-by: Matthieu Crapet <Matthieu.Crapet@ingenico.com>

diff --git a/libc/sysdeps/gnu/configure b/libc/sysdeps/gnu/configure
index e7f0e43..687beab 100644
--- a/libc/sysdeps/gnu/configure
+++ b/libc/sysdeps/gnu/configure
@@ -42,6 +42,6 @@ case "$prefix" in
   else
     libc_cv_localstatedir=$localstatedir
    fi
-  libc_cv_rootsbindir=/sbin
+  test -n "$libc_cv_rootsbindir" || libc_cv_rootsbindir=/sbin
   ;;
 esac
diff --git a/libc/sysdeps/gnu/configure.ac b/libc/sysdeps/gnu/configure.ac
index ce251df..57c1e77 100644
--- a/libc/sysdeps/gnu/configure.ac
+++ b/libc/sysdeps/gnu/configure.ac
@@ -42,6 +42,6 @@ case "$prefix" in
   else
     libc_cv_localstatedir=$localstatedir
    fi
-  libc_cv_rootsbindir=/sbin
+  test -n "$libc_cv_rootsbindir" || libc_cv_rootsbindir=/sbin
   ;;
 esac
-- 
2.0.0