* multi_sdd: WIP
* multi_sdd: CPU works
* multi_add: CUDA
* multi_add: simplify
* multi_add: Metal
* Metal: speed up mul_mat_id
For the Granite-1B MoE model PP-512 goes from
156 t/s to 890 t/s, so nearly a 6X speedup!
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Co-authored-by: Iwan Kawrakow <iwan.kawrakow@gmail.com>