CUDA: use MMVF for thin f16/bf16 mul_mat at small batch size (#29633)
* CUDA: use MMVF for thin f16/bf16 mul_mat at small batch size
Signed-off-by: ynankani <ynankani@nvidia.com>
* adjust kernel selection logic
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Signed-off-by: ynankani <ynankani@nvidia.com>
Co-authored-by: Johannes Gäßler <johannesg@5d6.de>