IDL4CPP11 — Don't require operator ==/!=

The spec says for structured types "A set of comparison operators, including at least "equal to" and "not equal to."", but that is not possible when the structure contains interfaces, valuetypes, valueboxes, abstract, all special types don't provide a operator==/!= so they can't be required when a structure contains any of these. This requirement has to be removed. CORBA doesn't provide equal for these special types because a local != doesn't mean that the references are not pointing to the same servant, object identity is not done through local pointers