Windows-MSVC.cmake: fix disabling of CMAKE_NINJA_CMCLDEPS_RC

This small patch avoids forcing CMAKE_NINJA_CMCLDEPS_RC to 1, making it possible to disable CMAKE_NINJA_CMCLDEPS_RC from a toolchain file. I have encountered the problem while trying to cross-compile from Linux to Windows using clang-cl, llvm-rc, and MSVC headers + libraries. Since cmcldeps is a tool currently only compiled (and ported) in the Windows version of CMake, activating it on Linux breaks the resource compiler invocation.