SYCL : Move to compile time oneMKL interface backend selection for NVIDIA backend...

SYCL : Move to compile time oneMKL interface backend selection for NVIDIA backend (llama/10584)

* [SYCL] Move to Compile Time backend selection on oneMKL Interface for NVIDIA backend

Move to compile time selection to backend to avoid latency at run time.
Add it to all mkl gemm calls and only for NVIDIA backend.

Signed-off-by: nscipione <redacted>
* Formatting

* Address PR comments to increase readibility

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Signed-off-by: nscipione <redacted>