Make Trepia compile

[grimmy]

This wasn't implemented in the original build and needs to be done yet.

[grimmy]

I'm working on this, it's a bit more than I hoped, but it's fine..

[grimmy]

After some more digging it's pretty clear that this never actually worked. It'd still be nice for it to compile, but at this point it's probably best to just have for historical purposes and to disable it but setting the meson feature to disabled.