Windows / macOS: simplify code

1. simplify resource management by using C++ RAII like GCC attribute extension `cleanup`
2. simplify HEKY reading

Actually `__attribute__((__cleanup__(cleanupFn)))` is supported on all major C compiler ( gcc, clang and icc ) except MSVC I only used it on Windows and macOS for now. Let's see if the project author like it.

src/detection/cpu/cpu_apple.c

@@ -15,7 +15,7 @@ static double getFrequency(const char* propName)
 
 static double detectCpuTemp(const FFstrbuf* cpuName)
 {
-    FFlist temps;
+    FF_LIST_AUTO_DESTROY temps;
     ffListInit(&temps, sizeof(FFTempValue));
 
     if(ffStrbufStartsWithS(cpuName, "Apple M1"))
@@ -38,7 +38,6 @@ static double detectCpuTemp(const FFstrbuf* cpuName)
         ffStrbufDestroy(&tempValue->deviceClass);
     }
     result /= temps.length;
-    ffListDestroy(&temps);
     return result;
 }