[WIP] Add OneformerFastImageProcessor (#38343)

* [WIP] OneformerFastImageProcessor

* update init

* Fully working oneformer image processor fast

* change Nearest to Neares exact interpolation where needed

* fix doc

---------

Co-authored-by: yonigozlan <yoni.gozlan@huggingface.co>
Co-authored-by: Yoni Gozlan <74535834+yonigozlan@users.noreply.github.com>

docs/source/en/model_doc/oneformer.md

@@ -38,7 +38,7 @@ This model was contributed by [Jitesh Jain](https://huggingface.co/praeclarumjj3
 
 ## Usage tips
 
--  OneFormer requires two inputs during inference: *image* and *task token*. 
+-  OneFormer requires two inputs during inference: *image* and *task token*.
 - During training, OneFormer only uses panoptic annotations.
 - If you want to train the model in a distributed environment across multiple nodes, then one should update the
   `get_num_masks` function inside in the `OneFormerLoss` class of `modeling_oneformer.py`. When training on multiple nodes, this should be
@@ -69,7 +69,14 @@ The resource should ideally demonstrate something new instead of duplicating an
 
 [[autodoc]] OneFormerImageProcessor
     - preprocess
-    - encode_inputs
+    - post_process_semantic_segmentation
+    - post_process_instance_segmentation
+    - post_process_panoptic_segmentation
+
+## OneFormerImageProcessorFast
+
+[[autodoc]] OneFormerImageProcessorFast
+    - preprocess
     - post_process_semantic_segmentation
     - post_process_instance_segmentation
     - post_process_panoptic_segmentation
@@ -87,4 +94,3 @@ The resource should ideally demonstrate something new instead of duplicating an
 
 [[autodoc]] OneFormerForUniversalSegmentation
     - forward
-