ide: add ide_device_add()

* Add ide_device_add() helper and convert host drivers to use it
  instead of open-coded variants.

* Make ide_pci_setup_ports() and do_ide_setup_pci_device()
  take 'u8 *idx' argument instead of 'ata_index_t *index'.

* Remove no longer needed ata_index_t.

* Unexport probe_hwif_init() and make it static.

* Unexport ide_proc_register_port().

There should be no functionality changes caused by this patch
(sgiioc4.c: ide_proc_register_port() requires hwif->present
 to be set and it won't be set if probe_hwif_init() fails).

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ppc/pmac.c b/drivers/ide/ppc/pmac.c
index c554793..959afe4 100644
--- a/drivers/ide/ppc/pmac.c
+++ b/drivers/ide/ppc/pmac.c
@@ -1039,6 +1039,7 @@
 {
 	struct device_node *np = pmif->node;
 	const int *bidp;
+	u8 idx[4] = { 0xff, 0xff, 0xff, 0xff };
 
 	pmif->cable_80 = 0;
 	pmif->broken_dma = pmif->broken_dma_warn = 0;
@@ -1163,10 +1164,9 @@
 		pmac_ide_setup_dma(pmif, hwif);
 #endif /* CONFIG_BLK_DEV_IDEDMA_PMAC */
 
-	/* We probe the hwif now */
-	probe_hwif_init(hwif);
+	idx[0] = hwif->index;
 
-	ide_proc_register_port(hwif);
+	ide_device_add(idx);
 
 	return 0;
 }