Log Message:
lang/nawk: downgrade to 20230909.

Partially revert previous commit, by downgrading the package to the
most recent release tag supporting ASCII encoded input files (and
processing strings as sequences of bytes).
This is needed by security/mozilla-rootcerts and likely other packages;
see https://mail-index.netbsd.org/tech-pkg/2023/09/17/msg028190.html.

This version incorporates all the changes described in the FIXES file up
to 2023-09-09, minus support for UTF-8 and comma-separated values (CSV)
input.