message: Fix logic on when to emit collective type but separate arg builder
  Got the comment right but the code wrong :/
diff: @@ -969,7 +969,7 @@ void OpEmitter::genSeparateArgParamBuilder() {
  // Emit separate arg build with collective type, unless there is only one
  // variadic result, in which case the above would have already generated
  // the same build method.
  - if (op.getNumResults() == 1 && !op.getResult(0).isVariadic())
  + if (!(op.getNumResults() == 1 && op.getResult(0).isVariadic()))
  emit(attrType, TypeParamKind::Collective, /*inferType=*/false);
  }
  }
  