[Reland] fix c10:TempFile APIs on Windows (#108508)
PR #106656 was reverted due to IOS failures. It seems that IOS builds don't have full support of std::filesystem. This PR discards std::filesystem changes and add temp file creation on Windows. It also moves the platform syscalls into a separate cpp file.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/108508
Approved by: https://github.com/ezyang
