Log Message:
mail/mew: update to 6.9

6.9 (2023-02-10)

Differences between Mew 6.9 and Mew 6.8

* Mew now supports Emacs 26.1 or later only.
* Supporting coming Emacs 29.
* Supporting "stunnel" 5.15.
* Supporting native compilation.
* `mew-smtp-port` now supports Unix domain socket.  If it is set to an
  absolute pathname such as "/var/run/msp.sock", Mew will use it as a
  Unix domain socket which supports SOCK_STREAM and understands SMTP.
  The value of `mew-smtp-server` will be ignored.  This feature requires
  `make-network-process` introduced since Emacs 22.
* Some bug fixes.