configure.ac warnings ("You should run autoupdate")

[gwestwood]

Describe the issue

When running autogen, a warning specifying "You should run autoupdate" appears.

Steps to reproduce

1. Run ./autogen.sh

Expected behavior (tell us what should happen)

Should complete without warnings.

Actual behavior (tell us what happens instead)

The following warning is displayed:

...
configure.ac:180: warning: The macro `AC_HELP_STRING' is obsolete.
configure.ac:180: You should run autoupdate.
../../lib/autoconf/general.m4:207: AC_HELP_STRING is expanded from...
../../lib/autoconf/general.m4:1473: AC_ARG_ENABLE is expanded from...
configure.ac:180: the top level
configure.ac:186: warning: The macro `AC_HELP_STRING' is obsolete.
configure.ac:186: You should run autoupdate.
...

What platform are you using (Linux, Windows, Mac)

Linux (Ubuntu 16.04.6 LTS)

git diff (after autoupdate):

diff --git a/configure.ac b/configure.ac
old mode 100755
new mode 100644
index dfaa862..9f18a93
--- a/configure.ac
+++ b/configure.ac
@@ -1,5 +1,5 @@
 dnl require autoconf 2.60 (AS_ECHO/AS_ECHO_N)
-AC_PREREQ([2.60])
+AC_PREREQ([2.69])
 define(_CLIENT_VERSION_MAJOR, 1)
 define(_CLIENT_VERSION_MINOR, 3)
 define(_CLIENT_VERSION_REVISION, 0)
@@ -178,14 +178,12 @@ AC_ARG_ENABLE([zmq],
   [use_zmq=yes])

 AC_ARG_ENABLE([ssse3],
-  [AC_HELP_STRING([--enable-ssse3],
-  [enable SSE3 optimizations (defaults is no)])],
+  [AS_HELP_STRING([--enable-ssse3],[enable SSE3 optimizations (defaults is no)])],
   [have_ssse3=${enableval}],
   [have_ssse3=no])

 AC_ARG_ENABLE([avx2],
-  [AC_HELP_STRING([--enable-avx2],
-  [enable AVX2 optimizations (defaults is no)])],
+  [AS_HELP_STRING([--enable-avx2],[enable AVX2 optimizations (defaults is no)])],
   [have_avx2=${enableval}],
   [have_avx2=no])

[andrewtookay]

Fixed in v1.3.1.0.