spleen: update to 1.9.2.

Spleen 1.9.2 (2023-02-15)

- Add Spleen ASCii logo header (Thanks H7!)
- Add SPDX short license identifier in sources and fonts
- Fix link to the Spleen package in AUR
- Use printf instead of echo for *BSD and Linux cross-compatibility
- Generate a specimen file for Spleen and include it in the repository
- Adjust trivias: the Haiku kernel debugger doesn't use Spleen anymore
- Update README to add a link to the MacPorts package
- Point the OpenBSD package link to openports.pl

(fcambus)