Remove OpenGL only IVfx::GetDriverInfo()
Remove few remaining referenecs to vfx_dx9 and vfx_gl
Remove GLSL and HLSL3 from the HLSL annotation parser
Delete vfx_gl vfx_dx9 files
Don't need per vfx generated antlr code or intermediate dirs
vfx cleanup, get rid of vmpi from vfxc and other shit
Restore coreclr AMSI patch with new hostfxr init