usbnet: smsc95xx: fix suspend failure

commit 76437214 upstream.

The three below functions:

	smsc95xx_enter_suspend0()
	smsc95xx_enter_suspend1()
	smsc95xx_enter_suspend2()

return > 0 in case of success, so they will cause smsc95xx_suspend()
to return > 0 and cause suspend failure.

The bug is introduced in commit 3b9f7d(smsc95xx: fix error handling
in suspend failure case).
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Cc: Steve Glendinning <steve.glendinning@shawell.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/net/usb/smsc95xx.c

@@ -1340,6 +1340,8 @@ static int smsc95xx_enter_suspend0(struct usbnet *dev)
 	ret = smsc95xx_read_reg_nopm(dev, PM_CTRL, &val);
 	if (ret < 0)
 		netdev_warn(dev->net, "Error reading PM_CTRL\n");
+	else
+		ret = 0;
 
 	return ret;
 }
@@ -1392,6 +1394,8 @@ static int smsc95xx_enter_suspend1(struct usbnet *dev)
 	ret = smsc95xx_write_reg_nopm(dev, PM_CTRL, val);
 	if (ret < 0)
 		netdev_warn(dev->net, "Error writing PM_CTRL\n");
+	else
+		ret = 0;
 
 	return ret;
 }
@@ -1413,6 +1417,8 @@ static int smsc95xx_enter_suspend2(struct usbnet *dev)
 	ret = smsc95xx_write_reg_nopm(dev, PM_CTRL, val);
 	if (ret < 0)
 		netdev_warn(dev->net, "Error writing PM_CTRL\n");
+	else
+		ret = 0;
 
 	return ret;
 }