6.5.1 build fails due to AVX intrinsics

C:\fbqt\source\qtbase\configure.bat -top-level -prefix C:/fbqt\builds\6.5.1\windows-x86_64-out -commercial -confirm-license -force-debug-info -debug -skip qtdatavis3d -skip qtdoc -skip qtvirtualkeyboard -skip qtwebengine -nomake examples -nomake tests -skip qtactiveqt -skip qtcoap -skip qtconnectivity -skip qtlottie -skip qtmqtt -skip qtopcua -skip qtqa -skip qtquicktimeline -skip qtquick3dphysics -skip qtscxml -skip qtsensors -skip qtserialbus -skip qtserialport -skip qtspeech -skip qttools -skip qttranslations -skip qtwayland -skip qtwebchannel -skip qtwebview -platform win32-clang-msvc -debug -opengl dynamic -qt-zlib -qt-libjpeg -qt-libpng -plugin-sql-sqlite -openssl-runtime -- -DCMAKE_EXE_LINKER_FLAGS=\"/manifest:no\" -DCMAKE_MODULE_LINKER_FLAGS=\"/manifest:no\" -DCMAKE_SHARED_LINKER_FLAGS=\"/manifest:no\" -DQT_FEATURE_ffmpeg=OFF -DQT_FEATURE_vulkan=ON -DCMAKE_VERBOSE_MAKEFILE=ON

C:\fbqt\source\qtbase\src\corelib\text\qstring.cpp(401,16): error: use of undeclared identifier '_mm_cvtepu8_epi16'; did you mean '_mm_cvtps_pi16'?
        return _mm_cvtepu8_epi16(data);
               ^~~~~~~~~~~~~~~~~
               _mm_cvtps_pi16
C:\tools\toolchains\LLVM12.0.1\lib\clang\12.0.1\include\xmmintrin.h(2869,1): note: '_mm_cvtps_pi16' declared here
_mm_cvtps_pi16(__m128 __a)
^
C:\fbqt\source\qtbase\src\corelib\text\qstring.cpp(401,16): error: cannot initialize return object of type '__m128i' (vector of 2 'long long' values) with an rvalue of type '__m64' (vector of 1 'long long' value)
        return _mm_cvtepu8_epi16(data);
               ^~~~~~~~~~~~~~~~~~~~~~~