ggml : add support for CPU f16->f16 GGML_OP_SET_ROWS (#25344)
* ggml : add support for CPU f16->f16 GGML_OP_SET_ROWS
* ggml : add missing type checks in f16 GGML_OP_SET_ROWS
* ggml : merge ggml_compute_forward_set_rows_f32() and ggml_compute_forward_set_rows_f16() into ggml_compute_forward_set_rows_impl()
* chore : replace assert() with GGML_ASSERT()
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Co-authored-by: Stanisław Szymczyk <sszymczy@gmail.com>