message: Fix build after previous change broke when CUDNN_VERSION < 7201.
diff: @@ -1267,6 +1267,7 @@ class CudnnRnnSequenceTensorDescriptor
  static port::StatusOr<CudnnRnnSequenceTensorDescriptor> Create(
  CUDAExecutor* parent, int max_seq_length, int batch_size, int data_size,
  const absl::Span<const int>& seq_lengths, cudnnDataType_t data_type) {
  +#if CUDNN_VERSION >= 7201
  CHECK_GT(max_seq_length, 0);
  int dims[] = {batch_size, data_size, 1};
  int strides[] = {dims[1] * dims[2], dims[2], 1};
  @@ -1276,7 +1277,6 @@ class CudnnRnnSequenceTensorDescriptor
  /*nbDims=*/sizeof(dims) / sizeof(dims[0]), /*dimA=*/dims,
  /*strideA=*/strides));
  const int* seq_lengths_array = seq_lengths.data();
  -#if CUDNN_VERSION >= 7201
  RNNDataDescriptor data_desc = CreateRNNDataDescriptor();
  float padding_fill = 0.0f;
  RETURN_IF_CUDNN_ERROR(cudnnSetRNNDataDescriptor(
  