llama : support all OpenELM models

* llama : add variable GQA and variable FFN sizes

Some metadata keys can now also be arrays to support setting
their value per-layer for models like OpenELM.

gguf-py/gguf/tensor_mapping.py

@@ -267,7 +267,6 @@ class TensorNameMap:
             "encoder.layers.{bid}.mlp.fc11",                          # nomic-bert
             "model.layers.{bid}.mlp.c_fc",                            # starcoder2
             "encoder.layer.{bid}.mlp.gated_layers_v",                 # jina-bert-v2
-            "transformer.layers.{bid}.ffn.proj_1",                    # openelm
             "model.layers.{bid}.residual_mlp.w3",                     # arctic
         ),