Undetected invalid comparison with type name

[treiher]

The use of a qualified type name in an expression should be detected as error. Currently, the following message specification is erroneously considered valid:

package Test is

   type T is mod 2 ** 8;

   type M is
      message
         A : T
            then null
               if A = Test::T;  --  Invalid
      end message;

end Test;