llama : support LiquidAI LFM2-MoE hybrid model (#16464)
* llama : support LiquidAI LFM2-MoE hybrid model
Add support for [LiquidAI/LFM2-8B-A1B](https://huggingface.co/LiquidAI/LFM2-8B-A1B) model.
For more information about models, please read [the blog post](https://www.liquid.ai/company/news).
[HF PR](https://github.com/huggingface/transformers/pull/41401)
[GGUFs](https://huggingface.co/LiquidAI/LFM2-8B-A1B-GGUF)
* Do not use defaultdict
* Address PR feedback