Disable the manifest bundling on Windows when cross-compiling on not-Windows. With this, it is possible to execute the link command from CMake which will use cmake to invoke the manifest tool to generate a manifest and pass that to the linker. git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@290836 91177308-0d34-0410-b5e6-96231b3b80d8