hw/pci-host/q35: Initialize PCI_HOST_BYPASS_IOMMU property from board code

hw/pci-host/q35: Initialize PCI_HOST_BYPASS_IOMMU property from board code

The Q35 PCI host already has a PCI_HOST_BYPASS_IOMMU property. However, the
host initializes this property itself by accessing global machine state,
thereby assuming it to be a PC machine. Avoid this by having board code
set this property.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230630073720.21297-6-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>