pkgdb for gnome software: add duplicate enties for Fedora Linux in f35+
    
    In F35,
    https://fedoraproject.org/wiki/Changes/Fedora_Linux_in_os-release
    changes the name of Fedora installs from Fedora to Fedora Linux.
    gnome-software uses this key to read this faugh pkgdb file to tell when
    to offer dist upgrades. We need to handle older versions that see
    "Fedora" as well as new ones that see "Fedora Linux".
    See https://pagure.io/fedora-infrastructure/issue/10154 for more info
    
    Signed-off-by: Kevin Fenzi <kevin@scrye.com>