[librsvg: 8/9] configure: Request autoconf 2.69+ (2012)

[Marge Bot <marge-bot src gnome org>]

commit 0776f4352941c8f31ebf1638f0684af2340204bb
Author: Ismael Luceno <ismael iodev co uk>
Date:   Sat Sep 11 18:40:43 2021 +0200

    configure: Request autoconf 2.69+ (2012)
    
    Part-of: <https://gitlab.gnome.org/GNOME/librsvg/-/merge_requests/586>

 configure.ac | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/configure.ac b/configure.ac
index 3279c452..02af26b0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,3 +1,5 @@
+AC_PREREQ([2.69])
+
 # Package version, the "human readable" version
 m4_define([rsvg_major_version],[2])
 m4_define([rsvg_minor_version],[51])