ide: remove ->data_phase field from ide_hwif_t

* Always use hwif->task->data_phase and remove ->data_phase
  field from ide_hwif_t.

* Remove superfluous REQ_TYPE_ATA_TASKFILE check from
  ide_pio_datablock() while at it.

There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c
index 45fc18f..3807616 100644
--- a/drivers/ide/ide-io.c
+++ b/drivers/ide/ide-io.c
@@ -310,13 +310,10 @@
 static ide_startstop_t execute_drive_cmd (ide_drive_t *drive,
 		struct request *rq)
 {
-	ide_hwif_t *hwif = drive->hwif;
 	ide_task_t *task = rq->special;
 
 	if (task) {
-		hwif->data_phase = task->data_phase;
-
-		switch (hwif->data_phase) {
+		switch (task->data_phase) {
 		case TASKFILE_MULTI_OUT:
 		case TASKFILE_OUT:
 		case TASKFILE_MULTI_IN: