fix mandelbench compile error

mandelbench/mandelbench.cpp

@@ -118,7 +118,7 @@ int main()
 
     auto types = mc.getSupportedTypes();
     for (auto [type, extension] : types) {
-        std::string extInfo = extension != mnd::CpuExtension::NONE ?
+        std::string extInfo = extension != mnd::NONE ?
             std::string(" ") + mnd::toString(extension) : "";
         REPORT_PERFORMANCE(mnd::toString(type) + extInfo + " [MIps]: ", benchmark(*mc.getCpuGenerator(type, extension)));
     }