TensorFlow MobileViT (#18555)

* initial implementation.

* add: working model till image classification.

* add: initial implementation that passes intg tests.

Co-authored-by: Amy <aeroberts4444@gmail.com>

* chore: formatting.

* add: tests (still breaking because of config mismatch).

Coo-authored-by: Yih <2521628+ydshieh@users.noreply.github.com>

* add: corrected tests and remaning changes.

* fix code style and repo consistency.

* address PR comments.

* address Amy's comments.

* chore: remove from_pt argument.

* chore: add full-stop.

* fix: TFLite model conversion in the doc.

* Update src/transformers/models/mobilevit/modeling_tf_mobilevit.py

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

* Update src/transformers/models/mobilevit/modeling_tf_mobilevit.py

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

* Update src/transformers/models/mobilevit/modeling_tf_mobilevit.py

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

* Update src/transformers/models/mobilevit/modeling_tf_mobilevit.py

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

* Update src/transformers/models/mobilevit/modeling_tf_mobilevit.py

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

* apply formatting.

* chore: remove comments from the example block.

* remove identation in the example.

Co-authored-by: Amy <aeroberts4444@gmail.com>
Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

docs/source/en/index.mdx

@@ -259,7 +259,7 @@ Flax), PyTorch, and/or TensorFlow.
 |            mBART            |       ✅       |       ✅       |       ✅        |         ✅         |      ✅      |
 |        Megatron-BERT        |       ❌       |       ❌       |       ✅        |         ❌         |      ❌      |
 |         MobileBERT          |       ✅       |       ✅       |       ✅        |         ✅         |      ❌      |
-|          MobileViT          |       ❌       |       ❌       |       ✅        |         ❌         |      ❌      |
+|          MobileViT          |       ❌       |       ❌       |       ✅        |         ✅         |      ❌      |
 |            MPNet            |       ✅       |       ✅       |       ✅        |         ✅         |      ❌      |
 |             MT5             |       ✅       |       ✅       |       ✅        |         ✅         |      ✅      |
 |             MVP             |       ✅       |       ✅       |       ✅        |         ❌         |      ❌      |