ide: fix host drivers depending on ide_generic to probe for interfaces (take 2)

* Add mpc8xx_ide_probe() to mpc8xx.c and call it from probe_for_hwifs().

* Convert ide_arm, ide-cris, ide-h8300, ide-pnp, buddha, falconide, gayle,
  macide, q40ide, cmd640 and mpc8xx host drivers to use ide_device_add().

  This removes dependency on ide_generic for these drivers so update
  ide/Kconfig accordingly.

v2:
* ide_arm build fix (s/ide_device_idx/ide_device_add/)
  (Thanks to Christoph Lameter <clameter@sgi.com> for reporting the problem).

Cc: Mikael Starvik <starvik@axis.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/legacy/gayle.c b/drivers/ide/legacy/gayle.c
index 705d0b8..ec53dc9 100644
--- a/drivers/ide/legacy/gayle.c
+++ b/drivers/ide/legacy/gayle.c
@@ -113,6 +113,7 @@
 void __init gayle_init(void)
 {
     int a4000, i;
+    u8 idx[4] = { 0xff, 0xff, 0xff, 0xff };
 
     if (!MACH_IS_AMIGA)
 	return;
@@ -183,7 +184,11 @@
 		    break;
 #endif /* CONFIG_BLK_DEV_IDEDOUBLER */
 	    }
+
+	    idx[i] = index;
 	} else
 	    release_mem_region(res_start, res_n);
     }
+
+    ide_device_add(idx);
 }