ggml-cpu: extend support for RVV floating-point kernels (#17318)
* cmake: add BF16 RVV flag for ggml-cpu
* ggml-cpu: add floating-point conversion kernels
* ggml: add floating-point kernels
Co-authored-by: Rehan Qasim <rehan.qasim@10xengineers.ai>
* ggml-cpu: fix lmul in vec_dot_bf16
* ggml-cpu: change redsum to lmul 4, fix leftover
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Co-authored-by: Rehan Qasim <rehan.qasim@10xengineers.ai>