Fixes a bug where `rundll32.exe advpack.dll,DelNodeRunDLL32 "c:\test",1` is only supposed to delete "test" if the directory is empty.
Also causes the [DelDirs Inf section](https://www.mdgx.com/INF_web/deldirs.htm) to work correctly.
Notes: - I changed the code so it ignores the result of `SetFileAttributesW` because the user might not have FILE_WRITE_ATTRIBUTES even if they have DELETE rights. This seems to match Windows (XP NTFS).