llama: Add support for Gemma2ForCausalLM (#8156)
* Inference support for Gemma 2 model family
* Update convert-hf-to-gguf.py, constants, and tensor mappings
* cleanup
* format fix
* Fix special token vocab bug
* Don't add space prefix
* fix deleted lines
* Update src/llama.cpp
Co-authored-by: slaren <slarengh@gmail.com>
* Add model type names
* Add control vector
* Fix model type identification
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Co-authored-by: Andrei Betlen <abetlen@gmail.com>
Co-authored-by: slaren <slarengh@gmail.com>
