Fix small CI failures

1) Only access UCI option if defined
2) disable -Werror for now.
3) disable a few target that don't have _mm_malloc.
4) Add profile-learn target, with small speedup.
5) just test on Linux + gcc (skip macOS, unclear openblas, skip linux+clang, unclear omp/std::filesystem).

src/nnue/evaluate_nnue.cpp

@@ -184,11 +184,13 @@ namespace Eval::NNUE {
 
     Initialize();
 
+#if defined(EVAL_NNUE)
     if (Options["SkipLoadingEval"])
     {
       std::cout << "info string SkipLoadingEval set to true, Net not loaded!" << std::endl;
       return true;
     }
+#endif
 
     fileName = evalFile;