How to know exactly what CPU dll is being loaded

[FerLuisxd]

I got paranoid as I didn't know what version was being loaded for the CPU backend

Proposed solution:

Allow for a way or function to get the selected CPU backend or print the evaluation.

What I found:

in:
transcribe.cpp\ggml\src\ggml-backend-reg.cpp

around lines ~524:

                    if (handle) {
                        auto score_fn = (ggml_backend_score_t) dl_get_sym(handle.get(), "ggml_backend_score");
                        if (score_fn) {
                            int s = score_fn();
                            if (s > 0) {
                                fprintf(stderr, "[ISA Probe] %s -> Score: %d (Supported)\n", path_str(entry.path().filename()).c_str(), s);
                            }
                            if (s > best_score) {
                                best_score = s;
                                best_path = entry.path();
                            }

Adding that print line to see the score if a debug parameter is passed.
So you can be sure that you are running the optimized one.

[cjpais]

I would pull this in if you submit a PR