ide: make remaining built-in only IDE host drivers modular (take 2)

* Make remaining built-in only IDE host drivers modular, add ide-scan-pci.c
  file for probing PCI host drivers registered with IDE core (special case
  for built-in IDE and CONFIG_IDEPCI_PCIBUS_ORDER=y) and then take care of
  the ordering in which all IDE host drivers are probed when IDE is built-in
  during link time.

* Move probing of gayle, falconide, macide, q40ide and buddha (m68k arch
  specific) host drivers, before PCI ones (no PCI on m68k), ide-cris (cris
  arch specific), cmd640 (x86 arch specific) and pmac (ppc arch specific).

* Move probing of ide-cris (cris arch specific) host driver before cmd640
  (x86 arch specific).

* Move probing of mpc8xx (ppc specific) host driver before ide-pnp (depends
  on ISA and none of ppc platform that use mpc8xx supports ISA) and ide-h8300
  (h8300 arch specific).

* Add "probe_vlb" kernel parameter to cmd640 host driver and update
  Documentation/ide.txt accordingly.

* Make IDE_ARM config option visible so it can also be disabled if needed.

* Remove bogus comment from ide.c while at it.

v2:
* Fix two issues spotted by Sergei:
  - replace ENOMEM error value by ENOENT in ide-h8300 host driver
  - fix MODULE_PARM_DESC() in cmd640 host driver

Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/legacy/macide.c b/drivers/ide/legacy/macide.c
index c1b7881..6b3e960 100644
--- a/drivers/ide/legacy/macide.c
+++ b/drivers/ide/legacy/macide.c
@@ -81,7 +81,7 @@
  * Probe for a Macintosh IDE interface
  */
 
-void __init macide_init(void)
+static int __init macide_init(void)
 {
 	hw_regs_t hw;
 	ide_hwif_t *hwif;
@@ -106,7 +106,7 @@
 				IRQ_BABOON_1);
 		break;
 	default:
-		return;
+		return -ENODEV;
 	}
 
 	hwif = ide_find_port(hw.io_ports[IDE_DATA_OFFSET]);
@@ -139,4 +139,8 @@
 
 		ide_device_add(idx);
 	}
+
+	return 0;
 }
+
+module_init(macide_init);