ssb: remove unreachable code

The return value of ssb_bus_unregister can only be 0 or -1, so this
condition if (err == -EBUSY) will not hold, so delete it.
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Acked-by: Michael Büsch <m@bues.ch>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1621306352-3632-1-git-send-email-tiantao6@hisilicon.com

drivers/ssb/main.c

@@ -434,9 +434,7 @@ void ssb_bus_unregister(struct ssb_bus *bus)
 	int err;
 
 	err = ssb_gpio_unregister(bus);
-	if (err == -EBUSY)
-		pr_debug("Some GPIOs are still in use\n");
-	else if (err)
+	if (err)
 		pr_debug("Can not unregister GPIO driver: %i\n", err);
 
 	ssb_buses_lock();