video: cirrusfb: remove unnecessary pci_set_drvdata()

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@ti.com>

drivers/video/cirrusfb.c

@@ -2159,7 +2159,6 @@ static int cirrusfb_pci_register(struct pci_dev *pdev,
 	if (!ret)
 		return 0;
 
-	pci_set_drvdata(pdev, NULL);
 	iounmap(info->screen_base);
 err_release_legacy:
 	if (release_io_ports)