fuzz: add i440fx fuzz targets

fuzz: add i440fx fuzz targets

These three targets should simply fuzz reads/writes to a couple ioports,
but they mostly serve as examples of different ways to write targets.
They demonstrate using qtest and qos for fuzzing, as well as using
rebooting and forking to reset state, or not resetting it at all.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-20-alxndr@bu.edu
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>