CUDA: fix numerical issue in tile FA kernel #16540
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Fixes issue described in #16528 (comment) .
The problem as far as I can tell are numerical issues for the rescaling of the VKQ accumulators with the inverse of the KQ sum at the end of the kernel. The input values in
test-backend-opsand the models I tested did not provoke this issue so I did not detect it in #16492 . The fix is to simply use FP32 arithmetic, the impact on performance is negligible since it's only done once per CUDA block.