vfio-pci: Fix use after free

Reported by 0-day test infrastructure.

Fixes: ecaa1f6a0154 ("vfio-pci: Add VGA arbiter client")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

drivers/vfio/pci/vfio_pci.c

@@ -953,6 +953,7 @@ static int vfio_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	if (ret) {
 		iommu_group_put(group);
 		kfree(vdev);
+		return ret;
 	}
 
 	if (vfio_pci_is_vga(pdev)) {