Add support for ARM64 on Windows

[hmartinez82]

Since ARM64 is already supported for MacOS, would it be possible to also support ARM64 for Windows?

[anthony-linaro]

Hi @hmartinez82, JFYI using #454 I am able to natively compile for Windows ARM64 platforms on my Thinkpad X13s, using the following:

From within a vcvarsall native ARM64 window, and the latest LLVM+Clang installed, having made and cd-ed to a build folder:

cmake -G"Ninja" .. -DCMAKE_C_COMPILER="clang-cl" -DCMAKE_CXX_COMPILER="clang-cl" -DCMAKE_C_FLAGS_INIT="--target=arm64-pc-windows-msvc" -DCMAKE_CXX_FLAGS_INIT="--target=arm64-pc-windows-msvc" -DTBB_ROOT=<path/to/tbb/install/dir> -DCMAKE_BUILD_TYPE=Release

Then

cmake --build . -j8

As a result all tests pass successfully within embree_verify.exe :)

One step closer to native blender!