ggml : Leverage the existing GGML_F32_VEC helpers to vectorize ggml_vec_set_f32 for faster fills (#16522)
* Leverage the existing GGML_F32_VEC helpers to broadcast the fill value across SIMD registers and store in vector-sized chunks, while retaining the scalar tail for leftover elements and non-SIMD builds.
* Vectorize additional f32 helper loops
* Normalize f32 helper tails for ggml vec ops
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Co-authored-by: Aaron <shelhamer.aaron@gmail.com>