swift

16994d14 - build: repair the build with VS2019 16.10.0

build: repair the build with VS2019 16.10.0 The newest VS2019 release updates CMake to 3.20, which picks up `llvm-mt` as a preferred manifest tool. However, we do not build `llvm-mt` with libxml2 support currently, which prevents the use of the just built manifest tool for building libdispatch. Explicitly opt into using the MSVC manifest-tool. Cherry-pick 2990e8bc070aee69b3a1cdecfd526ebf0f7ec5fa (cherry picked from commit d4d4d136a2c53cfe8828f85762c14def46ea5c99)