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/ide-cs.c b/drivers/ide/legacy/ide-cs.c
index 1a4b9e6..21bfac1 100644
--- a/drivers/ide/legacy/ide-cs.c
+++ b/drivers/ide/legacy/ide-cs.c
@@ -162,7 +162,7 @@
 {
     struct ide_host *host;
     ide_hwif_t *hwif;
-    int i;
+    int i, rc;
     hw_regs_t hw, *hws[] = { &hw, NULL, NULL, NULL };
 
     if (!request_region(io, 8, DRV_NAME)) {
@@ -184,12 +184,10 @@
     hw.chipset = ide_pci;
     hw.dev = &handle->dev;
 
-    host = ide_host_alloc(&idecs_port_info, hws);
-    if (host == NULL)
+    rc = ide_host_add(&idecs_port_info, hws, &host);
+    if (rc)
 	goto out_release;
 
-    ide_host_register(host, &idecs_port_info, hws);
-
     hwif = host->ports[0];
 
     if (hwif->present)