Add another boot passphrase entry needle variant for F25
    
    The F25 'desktopencrypt' images built by createhdds boot to a
    console passphrase entry screen, not graphical. F24 images
    built the same way boot to a graphical passphrase entry screen.
    I'm not sure why, but it's not really worth spending a lot of
    energy on, I don't think - let's just add a needle to cover
    this case.