The reference to RVSM doesn't have to be in a special part but only at the singular system. It might be deemed easier though to put it all together in one extra part, however that is something each operator has to decide on its own. The last two i worked with didn't do that, they just had a note at the relevant system in the MEL that you might be able to operate but only outside RVSM airspace, same as for other systems (de-icing equipment for example, you can operate without it but are not allowed to enter icing conditions). However TCAS is not one of them, it is not required for RVSM, but if you have TCAS II you need a certain version.