SHPCHP: fix __must_check warnings

Cc: Kristen Carlson Accardi <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/pci/hotplug/shpchp.h

···
 #define msg_button_cancel	"PCI slot #%s - action canceled due to button press.\n"
 
 /* sysfs functions for the hotplug controller info */
-extern void shpchp_create_ctrl_files	(struct controller *ctrl);
+extern int __must_check shpchp_create_ctrl_files(struct controller *ctrl);
 
 extern int	shpchp_sysfs_enable_slot(struct slot *slot);
 extern int	shpchp_sysfs_disable_slot(struct slot *slot);

drivers/pci/hotplug/shpchp_core.c

···
 		ctrl->speed = PCI_SPEED_33MHz;
 	}
 
-	shpchp_create_ctrl_files(ctrl);
+	rc = shpchp_create_ctrl_files(ctrl);
+	if (rc)
+		goto err_cleanup_slots;
 
 	return 0;
 
+err_cleanup_slots:
+	cleanup_slots(ctrl);
 err_out_release_ctlr:
 	ctrl->hpc_ops->release_ctlr(ctrl);
 err_out_free_ctrl:

drivers/pci/hotplug/shpchp_sysfs.c

···
 }
 static DEVICE_ATTR (ctrl, S_IRUGO, show_ctrl, NULL);
 
-void shpchp_create_ctrl_files (struct controller *ctrl)
+int __must_check shpchp_create_ctrl_files (struct controller *ctrl)
 {
-	device_create_file (&ctrl->pci_dev->dev, &dev_attr_ctrl);
+	return device_create_file (&ctrl->pci_dev->dev, &dev_attr_ctrl);
 }
 
 void shpchp_remove_ctrl_files(struct controller *ctrl)