hw/i386/vmport: Add device properties

No functional change.

This is done as a preparation for the following patches that will
introduce several device properties.
Reviewed-by: NNikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: NLiran Alon <liran.alon@oracle.com>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200312165431.82118-3-liran.alon@oracle.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

hw/i386/vmport.c

@@ -30,6 +30,7 @@
 
 #include "qemu/osdep.h"
 #include "hw/isa/isa.h"
+#include "hw/qdev-properties.h"
 #include "sysemu/hw_accel.h"
 #include "qemu/log.h"
 #include "vmport.h"
@@ -140,6 +141,10 @@ static void vmport_realizefn(DeviceState *dev, Error **errp)
     vmport_register(VMPORT_CMD_GETRAMSIZE, vmport_cmd_ram_size, NULL);
 }
 
+static Property vmport_properties[] = {
+    DEFINE_PROP_END_OF_LIST(),
+};
+
 static void vmport_class_initfn(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
@@ -147,6 +152,7 @@ static void vmport_class_initfn(ObjectClass *klass, void *data)
     dc->realize = vmport_realizefn;
     /* Reason: realize sets global port_state */
     dc->user_creatable = false;
+    device_class_set_props(dc, vmport_properties);
 }
 
 static const TypeInfo vmport_info = {