Another way to get doublicated events

This is a continuation of the story started in #1505 (closed) :

Another place, where we emit event twice for IDL5 and IDL6 devices is here: https://gitlab.com/tango-controls/cppTango/-/blob/d61c4bbef81c81e977a773ae5a2a90772717e582/src/server/eventsupplier.cpp#L495-527

And we have another 3 iterators, when we do the same.

Basically, the face, that we filter event by name and at the same time subscribe clients for differrent clients IDL with the same name is a mess...