x11/libXau: Update to 1.0.9

Update x11/libXau to 1.0.9.
Strip installed library.

The original PR suggested adding a variety of different licenses, all
MIT-like. After discussion with portmgr, it was decided that since the
liceneses are basically the same (only wording differs), we just tag it as
MIT licensed, without making a difference. This is already done.

PR: 235911 (based on)
Submitted by: Samy Mahmoudi
Sponsored by: B3 Init (zeising)