OBJECT_CHECK(PciHostState, ..., TYPE_PCI_HOST_BRIDGE) is exactly
what the PCI_HOST_BRIDGE macro does.  We can just use the macro
instead of using OBJECT_CHECK manually.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20210805193431.307761-7-ehabkost@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>