nubus: Simplify check in remove callback

The driver core only calls a remove callback when the device was
successfully bound (aka probed) before. So dev->driver is never NULL and
the respective check can just be dropped.
Acked-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210730191035.1455248-2-u.kleine-koenig@pengutronix.deSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/nubus/bus.c

@@ -33,7 +33,7 @@ static void nubus_device_remove(struct device *dev)
 {
 	struct nubus_driver *ndrv = to_nubus_driver(dev->driver);
 
-	if (dev->driver && ndrv->remove)
+	if (ndrv->remove)
 		ndrv->remove(to_nubus_board(dev));
 }