Merge branch 'net-mvmdio-avoid-error-message-for-optional-IRQ'

Chris Packham says:

====================
net: mvmdio: avoid error message for optional IRQ

I've gone ahead an sent a revert. This is the same as the original v1 except
I've added Andrew's review to the commit message.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/mvmdio.c

@@ -364,8 +364,8 @@ static int orion_mdio_probe(struct platform_device *pdev)
 		writel(MVMDIO_ERR_INT_SMI_DONE,
 			dev->regs + MVMDIO_ERR_INT_MASK);
 
-	} else if (dev->err_interrupt < 0) {
-		ret = dev->err_interrupt;
+	} else if (dev->err_interrupt == -EPROBE_DEFER) {
+		ret = -EPROBE_DEFER;
 		goto out_mdio;
 	}