[PATCH] maint: ensure autoconf-latest.* links stay up-to-date

[Eric Blake]

* cfg.mk (GNUPLOADFLAGS): New.
https://lists.gnu.org/archive/html/autoconf/2021-05/msg00006.html
---

I just pushed this, after coming up with something similar for m4.

 cfg.mk | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/cfg.mk b/cfg.mk
index 0d4ec728..6a89e489 100644
--- a/cfg.mk
+++ b/cfg.mk
@@ -86,6 +86,9 @@ update-release-year:
 # Prevent incorrect NEWS edits.
 old_NEWS_hash = 981169afdd2c97642125938f80a26b7f

+# Update autoconf-latest.tar.* symlinks during 'make stable/beta'.
+GNUPLOADFLAGS = --symlink-regex
+
 exclude_file_name_regexp--sc_prohibit_undesirable_word_seq = \
   ^(maint\.mk|build-aux/texinfo\.tex)$$
 exclude_file_name_regexp--sc_prohibit_test_minus_ao = \
-- 
2.31.1