The PIIX3 is not tied to the i440FX and can even be used without it.
Move its creation to the machine code (pc_piix.c).
We have now removed the last trace of southbridge code in the i440FX
northbridge.
Reviewed-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
48bc99a09c