[ide] fix error handling in probe_hwif_init() and sgiioc4 driver

From: Prarit Bhargava <prarit@sgi.com>

I discovered an issue where a hwif_init() failure lead to /proc/ide files
being created for devices that failed probes.  This resulted in
oops/WARN_ON/BUG_ON executions through the kernel depending on what
actions were on going.

slightly changed by me (bart)
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/ide/ide-probe.c

@@ -841,7 +841,11 @@ int probe_hwif_init_with_fixup(ide_hwif_t *hwif, void (*fixup)(ide_hwif_t *hwif)
 	if (fixup)
 		fixup(hwif);
 
-	hwif_init(hwif);
+	if (!hwif_init(hwif)) {
+		printk(KERN_INFO "%s: failed to initialize IDE interface\n",
+				 hwif->name);
+		return -1;
+	}
 
 	if (hwif->present) {
 		u16 unit = 0;

drivers/ide/pci/sgiioc4.c

@@ -669,7 +669,8 @@ sgiioc4_ide_setup_pci_device(struct pci_dev *dev, ide_pci_device_t * d)
 		printk(KERN_INFO "%s: %s Bus-Master DMA disabled\n",
 		       hwif->name, d->name);
 
-	probe_hwif_init(hwif);
+	if (probe_hwif_init(hwif))
+		return -EIO;
 
 	/* Create /proc/ide entries */
 	create_proc_ide_interfaces();