ide: drop "PIO data" argument from ide_get_best_pio_mode()

* Drop no longer needed "PIO data" argument from ide_get_best_pio_mode()
  and convert all users accordingly.

* Remove no longer needed ide_pio_data_t.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/pci/cs5530.c b/drivers/ide/pci/cs5530.c
index 643d66c..a75c14a 100644
--- a/drivers/ide/pci/cs5530.c
+++ b/drivers/ide/pci/cs5530.c
@@ -82,7 +82,7 @@
 
 static void cs5530_tuneproc (ide_drive_t *drive, u8 pio)	/* pio=255 means "autotune" */
 {
-	pio = ide_get_best_pio_mode(drive, pio, 4, NULL);
+	pio = ide_get_best_pio_mode(drive, pio, 4);
 
 	if (cs5530_set_xfer_mode(drive, XFER_PIO_0 + pio) == 0)
 		cs5530_tunepio(drive, pio);