phy: remove an unneeded condition

It used to be that bus->irq was a pointer but after e7f4dc3536a4
('mdio: Move allocation of interrupts into core') it's an array inside
the mdio struct, so it can never be NULL.  Let's remove the check.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 3193006..903737a 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -340,7 +340,7 @@
 	dev->phy_id = phy_id;
 	if (c45_ids)
 		dev->c45_ids = *c45_ids;
-	dev->irq = bus->irq ? bus->irq[addr] : PHY_POLL;
+	dev->irq = bus->irq[addr];
 	dev_set_name(&mdiodev->dev, PHY_ID_FMT, bus->id, addr);
 
 	dev->state = PHY_DOWN;