Fixing (1) tensor size mismatch and (2) missing prepare_cos_sin issues for Phi-3.5

[mrezavand]

Solving the two issues reported in: https://jira.habana-labs.com/browse/SW-221986

1. vLLM both offline and online inferencing of the "microsoft/Phi-3.5-mini-instruct" model firstly complained about a missing 'prepare_cos_sin' method, that is necessary for the rotational position embeddings (RoPE):

ERROR 03-11 10:04:32 engine.py:389]   File "/home/vllm-fork/vllm/worker/hpu_model_runner.py", line 424, in _prepare_cos_sin
ERROR 03-11 10:04:32 engine.py:389]     raise AttributeError(
ERROR 03-11 10:04:32 engine.py:389] AttributeError: The module at the end of the path does not have a 'prepare_cos_sin' method.

2. Model fails due the a size mismatch:

File "/home/vllm-fork/vllm/model_executor/layers/rotary_embedding.py", line 641, in forward
    query_rot = query_rot * cos + _rotate_neox(query_rot) * sin
RuntimeError: The size of tensor a (96) must match the size of tensor b (1024) at non-singleton dimension 3 

[michalkuligowski]

/run-gaudi-tests

[mrezavand]

@michalkuligowski I just fix the ruff issue.

[michalkuligowski]

/run-gaudi-tests

[michalkuligowski]

/run-gaudi-tests

[michalkuligowski]

/run-gaudi-tests