Add CMake scripts to D3D11/D3D12 demos

[M2002RST]

This change helps other users, one command can generate a VS solution regardless of which Visual Studio IDE users have.

e.g.
cd ./demo/d3d12
cmake -S ./ -B ./cmake

[igromanru]

I don't know much about CMake. But shouldn't there be a CMakeLists.txt ?
How do I build it with Native Tools Command Prompt from VS 2022?