message: Remove link to non-existent doc.
diff: @@ -917,8 +917,7 @@ def convolution(
  input channel number, and z is the N-D spatial offset within the filter. Here,
  `padded_input` is obtained by zero padding the input using an effective
  spatial filter shape of `(spatial_filter_shape-1) * dilation_rate + 1` and
  - output striding `strides` as described in the
  - [comment here](https://tensorflow.org/api_guides/python/nn#Convolution).
  + output striding `strides`.
  In the case that `data_format` does start with `"NC"`, the `input` and output
  (but not the `filter`) are simply transposed as follows:
  