seccomp: Always try to do the socket filtering, but don't fail if not supported
seccomp: Always try to do the socket filtering, but don't fail if not supported

This is better than guessing if it will work before.
However, we need to add the rule with _rule_add_exact, or it can try
to do something else which breaks the app.

alexlarsson/xdg-app,handsome-feng/flatpak,GeorgesStavracas/flatpak,matthiasclasen/flatpak,alexlarsson/xdg-app,matthiasclasen/xdg-app,flatpak/flatpak,amigadave/flatpak,handsome-feng/flatpak,amigadave/flatpak,flatpak/flatpak,handsome-feng/flatpak,matthiasclasen/flatpak,flatpak/flatpak,matthiasclasen/xdg-app,amigadave/flatpak,GeorgesStavracas/flatpak,matthiasclasen/flatpak,handsome-feng/flatpak,matthiasclasen/flatpak,GeorgesStavracas/flatpak,flatpak/flatpak,matthiasclasen/flatpak,GeorgesStavracas/flatpak,alexlarsson/xdg-app,amigadave/flatpak,alexlarsson/xdg-app,handsome-feng/flatpak,matthiasclasen/xdg-app,matthiasclasen/xdg-app,flatpak/flatpak,GeorgesStavracas/flatpak