PowerPC: Enable MMA for BF16 in llamafile_sgemm#13146

shalinib-ibm wants to merge 2 commits intoggml-org:masterggml-org/llama.cpp:masterfrom

shalinib-ibm:ppc_bf16_llamafileshalinib-ibm/llama.cpp:ppc_bf16_llamafileCopy head branch name to clipboard