ravedude: Update CHANGELOG

Author: Rahix

ravedude/CHANGELOG.md

@@ -9,8 +9,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added a `general.console-port` option with a corresponding
   `-C`/`--console-port` CLI option to set a console port that's separate from
   the programming port ([#683]).
+- Support for the AVR `butterfly` board ([#685]).
 
 [#683]: https://github.com/Rahix/avr-hal/pull/683
+[#685]: https://github.com/Rahix/avr-hal/pull/685
 
 
 ## [0.2.1] - 2025-08-31