vfio/pci: Fix unchecked return value

There's nothing we can do different if pci_load_and_free_saved_state()
fails, other than maybe print some log message, but the actual re-load
of the state is an unnecessary step here since we've only just saved
it.  We can cleanup a coverity warning and eliminate the unnecessary
step by freeing the state ourselves.

Detected by Coverity: CID 753101
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

drivers/vfio/pci/vfio_pci.c

@@ -57,7 +57,8 @@ static int vfio_pci_enable(struct vfio_pci_device *vdev)
 
 	ret = vfio_config_init(vdev);
 	if (ret) {
-		pci_load_and_free_saved_state(pdev, &vdev->pci_saved_state);
+		kfree(vdev->pci_saved_state);
+		vdev->pci_saved_state = NULL;
 		pci_disable_device(pdev);
 		return ret;
 	}