libata: handle pci_enable_device() failure while resuming

Handle pci_enable_device() failure while resuming.  This patch kills
the "ignoring return value of 'pci_enable_device'" warning message and
propagates __must_check through ata_pci_device_do_resume().

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/include/linux/libata.h b/include/linux/libata.h
index dab4dc5..a8ecaaa 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -716,7 +716,7 @@
 			     unsigned int n_ports);
 extern void ata_pci_remove_one (struct pci_dev *pdev);
 extern void ata_pci_device_do_suspend(struct pci_dev *pdev, pm_message_t mesg);
-extern void ata_pci_device_do_resume(struct pci_dev *pdev);
+extern int __must_check ata_pci_device_do_resume(struct pci_dev *pdev);
 extern int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg);
 extern int ata_pci_device_resume(struct pci_dev *pdev);
 extern int ata_pci_clear_simplex(struct pci_dev *pdev);