* ggml: uniformize im2col dst_type for all conv ops
* Update ggml/src/ggml.c
Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>
* ggml : uniformize im2col casting logic across all conv ops
* fix : allow im2col_f16 to accept any kernel type
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Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>