ggml-hip: enable -funsafe-math-optimizations (#24668)
CUDA is compiled with fast math and AMD/HIP is not — this flag lets AMD use fast math too.
We can't use -ffast-math: it implies -ffinite-math-only, which won't compile (ggml uses INFINITY for masking) and produces NaNs. -funsafe-math-optimizations gives the speedup without the NaN problems.
Co-authored-by: Mark Caldwell <mark@cloudhands.ai>
