message: [tf.data] Fix documentation.
diff: @@ -223,7 +223,7 @@ class MultiDeviceIterator(object):
  dataset: The input dataset to be iterated over.
  devices: The list of devices to fetch data to.
  max_buffer_size: Maximum size of the host side per device buffer to keep.
  - prefetch_buffer_size: if > 1, then we setup a buffer on each device to
  + prefetch_buffer_size: if > 0, then we setup a buffer on each device to
  prefetch into.
  source_device: The host device to place the `dataset` on. In order to
  prevent deadlocks, if the prefetch_buffer_size is greater than the
  @@ -481,7 +481,7 @@ class OwnedMultiDeviceIterator(composite_tensor.CompositeTensor):
  dataset: The input dataset to be iterated over.
  devices: The list of devices to fetch data to.
  max_buffer_size: Maximum size of the host side per device buffer to keep.
  - prefetch_buffer_size: if > 1, then we setup a buffer on each device to
  + prefetch_buffer_size: if > 0, then we setup a buffer on each device to
  prefetch into.
  source_device: The host device to place the `dataset` on. In order to
  prevent deadlocks, if the prefetch_buffer_size is greater than the
  