[MLIR] Hide FailureOr::hasValue()

[csigg]

Summary

Optional<T>::hasValue() is deprecated and should be private like has_value().

mlir/include/mlir/Support/LogicalResult.h

public:
   FailureOr(const FailureOr<U> &other)
       : Optional<T>(failed(other) ? Optional<T>() : Optional<T>(*other)) {}
 
   operator LogicalResult() const { return success(this->has_value()); }
 
 private:
   /// Hide the bool conversion as it easily creates confusion.
   using Optional<T>::operator bool;
+  using Optional<T>::hasValue;
   using Optional<T>::has_value;
 };
 
 /// Wrap a value on the success path in a FailureOr of the same value type.
 template <typename T,
           typename = std::enable_if_t<!std::is_convertible_v<T, bool>>>
 inline auto success(T &&t) {
   return FailureOr<std::decay_t<T>>(std::forward<T>(t));