Why use "enum struct" instead of "enum" for DuploTrainBaseSound?

[fredlcore]

legoino/src/Lpf2HubConst.h

Line 224 in 434b74f

enum struct DuploTrainBaseSound

For Color you use an enum which makes code much easier to read as you can just use RED or CYAN to refer to the respective colors. For the sounds, we have to write DuploTrainBaseSound::BRAKE which makes reading a bit more clumsy. It's of course nothing major and maybe I just overlook an important aspect, but if it is exchangeable, why not use a simple enum here as well?