NEWS: Briefly mention a few more improvements.

Specifically, this is meant to cover these commits:

2b56e8c2 autoreconf: don’t fail if gtkdocize is unavailable (#110503)
912567e9 autoreconf: require word boundaries when grepping for macros (#111271)
4774e6bb autoreconf: Adapt to the on-disk situation after autopoint has run.
f0d97fb5 autoreconf: Invoke autopoint in more situations.

and

9a6c58cf Rename version.m4 to autoconf_version.m4.