atlx: fix warning in drivers/net/atlx/atl2.c

fix this warning:

  drivers/net/atlx/atl2.c: In function ‘atl2_request_irq’:
  drivers/net/atlx/atl2.c:644: warning: unused variable ‘err’

'err' is unused in the !CONFIG_PCI_MSI case.

Instead of further increasing the #ifdeffery in this function,
restructure the code a bit and get rid of the #ifdef. This
relies on the fact that pci_enable_msi() will always fail in
the !CONFIG_PCI_MSI case.

There should be no change in driver behavior.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/atlx/atl2.c

@@ -644,7 +644,6 @@ static int atl2_request_irq(struct atl2_adapter *adapter)
 	int flags, err = 0;
 
 	flags = IRQF_SHARED;
-#ifdef CONFIG_PCI_MSI
 	adapter->have_msi = true;
 	err = pci_enable_msi(adapter->pdev);
 	if (err)
@@ -652,7 +651,6 @@ static int atl2_request_irq(struct atl2_adapter *adapter)
 
 	if (adapter->have_msi)
 		flags &= ~IRQF_SHARED;
-#endif
 
 	return request_irq(adapter->pdev->irq, &atl2_intr, flags, netdev->name,
 		netdev);