vfio: fix duplicate function call

When vfio device is reset(encounter FLR, or bus reset), if need to do
bus reset(vfio_pci_hot_reset_one is called), vfio_pci_pre_reset &
vfio_pci_post_reset will be called twice.
Signed-off-by: NCao jin <caoj.fnst@cn.fujitsu.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>

hw/vfio/pci.c

@@ -1951,7 +1951,9 @@ static int vfio_pci_hot_reset(VFIOPCIDevice *vdev, bool single)
 
     trace_vfio_pci_hot_reset(vdev->vbasedev.name, single ? "one" : "multi");
 
-    vfio_pci_pre_reset(vdev);
+    if (!single) {
+        vfio_pci_pre_reset(vdev);
+    }
     vdev->vbasedev.needs_reset = false;
 
     info = g_malloc0(sizeof(*info));
@@ -2109,7 +2111,9 @@ out:
         }
     }
 out_single:
-    vfio_pci_post_reset(vdev);
+    if (!single) {
+        vfio_pci_post_reset(vdev);
+    }
     g_free(info);
 
     return ret;