Add GritLM as supported models. (ggml-org#6513)

Author: dranger003

README.md

@@ -119,6 +119,7 @@ Typically finetunes of the base models below are supported as well.
 - [x] [Xverse](https://huggingface.co/models?search=xverse)
 - [x] [Command-R](https://huggingface.co/CohereForAI/c4ai-command-r-v01)
 - [x] [SEA-LION](https://huggingface.co/models?search=sea-lion)
+- [x] [GritLM-7B](https://huggingface.co/GritLM/GritLM-7B) + [GritLM-8x7B](https://huggingface.co/GritLM/GritLM-8x7B)
 
 **Multimodal models:**