vfio/ccw: fix initialization of the Object DeviceState pointer in the common base-device

Commit 7da624e2 ("vfio: Test realized when using VFIOGroup.device_list
iterator") introduced a pointer to the Object DeviceState in the VFIO
common base-device and skipped non-realized devices as we iterate
VFIOGroup.device_list. While it missed to initialize the pointer for
the vfio-ccw case. Let's fix it.

Fixes: 7da624e2 ("vfio: Test realized when using VFIOGroup.device_list
                  iterator")

Cc: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: NHalil Pasic <pasic@linux.vnet.ibm.com>
Signed-off-by: NDong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Reviewed-by: NAlex Williamson <alex.williamson@redhat.com>
Message-Id: <20170718014926.44781-3-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

hw/vfio/ccw.c

@@ -338,6 +338,7 @@ static void vfio_ccw_realize(DeviceState *dev, Error **errp)
     vcdev->vdev.type = VFIO_DEVICE_TYPE_CCW;
     vcdev->vdev.name = g_strdup_printf("%x.%x.%04x", cdev->hostid.cssid,
                                        cdev->hostid.ssid, cdev->hostid.devid);
+    vcdev->vdev.dev = dev;
     QLIST_FOREACH(vbasedev, &group->device_list, next) {
         if (strcmp(vbasedev->name, vcdev->vdev.name) == 0) {
             error_setg(&err, "vfio: subchannel %s has already been attached",