ide: add ide_legacy_device_add() helper

Add ide_legacy_device_add() helper for use by legacy VLB host drivers
(+ convert them to use it).

There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/include/linux/ide.h b/include/linux/ide.h
index a612c89..68e5a00 100644
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -1213,6 +1213,7 @@
 
 int ide_device_add_all(u8 *idx, const struct ide_port_info *);
 int ide_device_add(u8 idx[4], const struct ide_port_info *);
+int ide_legacy_device_add(const struct ide_port_info *);
 void ide_port_unregister_devices(ide_hwif_t *);
 void ide_port_scan(ide_hwif_t *);