[GPU] Fixup GEMM strategy override

[kealan-barbieri]

Description

Use strategy values rather than driver_info which may be uninitialized.

Checklist

General

• [ ] Do all unit and benchdnn tests (make test and make test_benchdnn_*) pass locally for each commit?
• [x] Have you formatted the code using clang-format?

[Simonsays095]

In what cases are these member variables of driver_info_ uninitialized? From what I understand, all CommonDriverInfo models use these variables (not 100% sure about this), and it gets initialized in the entry_ and copied into driver_info_ (either from the strategy or the entry) a few lines earlier in update_driver_info.

[kealan-barbieri]

@Simonsays095 there are some cases where kInterleave is set but kInterleaveChunk is not so in driverInfo unroll for K dim actually gets set to 0 after its been initialized to the non-zero default value from the strategy, looking into whether theres a better fix within that initialization.

[Simonsays095]

This is included as part of #3616.