Update README.md

typo in model name and fix path since they have regrouped the llms under the llms folder.

README.md

@@ -25,10 +25,10 @@ git clone https://github.com/ml-explore/mlx-examples.git
 
 # Download model
 export HF_HUB_ENABLE_HF_TRANSFER=1
-huggingface-cli download --local-dir-use-symlinks False --local-dir mlx_model mlx-community/Mistral-7B-Instruct-v0.2
+huggingface-cli download --local-dir-use-symlinks False --local-dir mlx_model mlx-community/Mistral-7B-Instruct-v0.2-4-bit
 
 # Run example
-python mlx-examples/mistral/mistral.py --prompt "My name is"
+python mlx-examples/llms/mistral/mistral.py --prompt "My name is"
 ```
 
 The rest of this model card was copied from the [original repository](https://huggingface.co/mistralai/Mistral-7B-Instruct-v0.2).