[clang][dataflow][NFC] Fix stale comments. (#71654)

  /// Creates a `T` (some subclass of `StorageLocation`), forwarding `args` to

  /// the constructor, and returns a reference to it.

  ///

  /// The `DataflowAnalysisContext` takes ownership of the created object. The

  /// object will be destroyed when the `DataflowAnalysisContext` is destroyed.

  /// The `Arena` takes ownership of the created object. The object will be

  /// destroyed when the `Arena` is destroyed.

  template <typename T, typename... Args>

  std::enable_if_t<std::is_base_of<StorageLocation, T>::value, T &>

  create(Args &&...args) {

  /// Creates a `T` (some subclass of `Value`), forwarding `args` to the

  /// constructor, and returns a reference to it.

  ///

  /// The `DataflowAnalysisContext` takes ownership of the created object. The

  /// object will be destroyed when the `DataflowAnalysisContext` is destroyed.

  /// The `Arena` takes ownership of the created object. The object will be

  /// destroyed when the `Arena` is destroyed.

  template <typename T, typename... Args>

  std::enable_if_t<std::is_base_of<Value, T>::value, T &>

  create(Args &&...args) {