ide: add struct ide_io_ports (take 3)

* Add struct ide_io_ports and use it instead of `unsigned long io_ports[]`
  in ide_hwif_t.

* Rename io_ports[] in hw_regs_t to io_ports_array[].

* Use un-named union for 'unsigned long io_ports_array[]' and 'struct
  ide_io_ports io_ports' in hw_regs_t.

* Remove IDE_*_OFFSET defines.

v2:
* scc_pata.c build fix from Stephen Rothwell.

v3:
* Fix ctl_adrr typo in Sparc-specific part of ns87415.c.
  (Noticed by Andrew Morton)

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/legacy/macide.c b/drivers/ide/legacy/macide.c
index 26546d0..1f527bb 100644
--- a/drivers/ide/legacy/macide.c
+++ b/drivers/ide/legacy/macide.c
@@ -72,9 +72,9 @@
 	memset(hw, 0, sizeof(*hw));
 
 	for (i = 0; i < 8; i++)
-		hw->io_ports[i] = base + i * 4;
+		hw->io_ports_array[i] = base + i * 4;
 
-	hw->io_ports[IDE_CONTROL_OFFSET] = base + IDE_CONTROL;
+	hw->io_ports.ctl_addr = base + IDE_CONTROL;
 
 	hw->irq = irq;
 	hw->ack_intr = ack_intr;