Don't define Neon* functions when USE_NEON define is missing.

PiperOrigin-RevId: 254098359

tensorflow/lite/kernels/internal/optimized/neon_tensor_utils_impl.h

@@ -27,6 +27,8 @@ limitations under the License.
 namespace tflite {
 namespace tensor_utils {
 
+#ifdef USE_NEON
+
 // Multiply a matrix by a batch vector, and store results in a batch-size
 // vector.
 void NeonMatrixBatchVectorMultiplyAccumulate(const float* matrix, int m_rows,
@@ -119,6 +121,8 @@ void NeonVectorShiftLeft(float* vector, int v_size, float shift_value);
 void NeonReductionSumVector(const float* input_vector, float* output_vector,
                             int output_size, int reduction_size);
 
+#endif  // USE_NEON
+
 }  // namespace tensor_utils
 }  // namespace tflite