ide: add ide_host_add() helper

Add ide_host_add() helper which does ide_host_alloc()+ide_host_register(),
then convert ide_setup_pci_device[s](), ide_legacy_device_add() and some
host drivers to use it.

While at it:

* Fix ide_setup_pci_device[s](), ide_arm.c, gayle.c, ide-4drives.c,
  macide.c, q40ide.c, cmd640.c and cs5520.c to return correct error value.

* -ENOENT -> -ENOMEM in rapide.c, ide-h8300.c, ide-generic.c, au1xxx-ide.c
  and pmac.c

* -ENODEV -> -ENOMEM in palm_bk3710.c, ide_platform.c and delkin_cb.c

* -1 -> -ENOMEM in ide-pnp.c

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/legacy/macide.c b/drivers/ide/legacy/macide.c
index b49cf8c..a0bb167 100644
--- a/drivers/ide/legacy/macide.c
+++ b/drivers/ide/legacy/macide.c
@@ -92,7 +92,6 @@
 static int __init macide_init(void)
 {
 	ide_ack_intr_t *ack_intr;
-	struct ide_host *host;
 	unsigned long base;
 	int irq;
 	hw_regs_t hw, *hws[] = { &hw, NULL, NULL, NULL };
@@ -125,11 +124,7 @@
 
 	macide_setup_ports(&hw, base, irq, ack_intr);
 
-	host = ide_host_alloc(NULL, hws);
-	if (host)
-		ide_host_register(host, NULL, hws);
-
-	return 0;
+	return ide_host_add(NULL, hws, NULL);
 }
 
 module_init(macide_init);