We have a virtio-s390 and a virtio-ccw machine in QEMU. Both use vastly
different ways to do I/O. Having the same firmware blob for both doesn't
really make any sense.
Instead, let's parametrize the firmware file name, so that we can have
different blobs for different machines.
Signed-off-by: Alexander Graf <agraf@suse.de>
d0249ce5a8