Override SSM_A op for Qwen3 Next to reduce splits (#17587)

Override SSM_A op for Qwen3 Next to reduce splits (#17587)

* Override SSM_A op for Qwen3 Next to reduce splits

* New tensor mapping SSM_A_NOSCAN for SSM_A used outside of OP_SSM_SCAN context.

* Update src/llama-model.cpp

Co-authored-by: Sigbjørn Skjæret <redacted>
* Update src/llama-model.cpp

Co-authored-by: Sigbjørn Skjæret <redacted>
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Co-authored-by: Sigbjørn Skjæret <redacted>