ide: remove ide_task_t typedef

While at it:
- rename struct ide_task_s to struct ide_cmd
- remove stale comments from idedisk_{read_native,set}_max_address()
- drop unused 'cmd' argument from ide_{cmd,task}_ioctl()
- drop unused 'task' argument from tx4939ide_tf_load_fixup()
- rename ide_complete_task() to ide_complete_cmd()
- use consistent naming for struct ide_cmd variables

There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ide-park.c b/drivers/ide/ide-park.c
index cddc7c7..63c77f9 100644
--- a/drivers/ide/ide-park.c
+++ b/drivers/ide/ide-park.c
@@ -63,10 +63,10 @@
 
 ide_startstop_t ide_do_park_unpark(ide_drive_t *drive, struct request *rq)
 {
-	ide_task_t task;
-	struct ide_taskfile *tf = &task.tf;
+	struct ide_cmd cmd;
+	struct ide_taskfile *tf = &cmd.tf;
 
-	memset(&task, 0, sizeof(task));
+	memset(&cmd, 0, sizeof(cmd));
 	if (rq->cmd[0] == REQ_PARK_HEADS) {
 		drive->sleep = *(unsigned long *)rq->special;
 		drive->dev_flags |= IDE_DFLAG_SLEEPING;
@@ -75,14 +75,15 @@
 		tf->lbal = 0x4c;
 		tf->lbam = 0x4e;
 		tf->lbah = 0x55;
-		task.tf_flags |= IDE_TFLAG_CUSTOM_HANDLER;
+		cmd.tf_flags |= IDE_TFLAG_CUSTOM_HANDLER;
 	} else		/* cmd == REQ_UNPARK_HEADS */
 		tf->command = ATA_CMD_CHK_POWER;
 
-	task.tf_flags |= IDE_TFLAG_TF | IDE_TFLAG_DEVICE;
-	task.rq = rq;
-	task.data_phase = TASKFILE_NO_DATA;
-	return do_rw_taskfile(drive, &task);
+	cmd.tf_flags |= IDE_TFLAG_TF | IDE_TFLAG_DEVICE;
+	cmd.rq = rq;
+	cmd.data_phase = TASKFILE_NO_DATA;
+
+	return do_rw_taskfile(drive, &cmd);
 }
 
 ssize_t ide_park_show(struct device *dev, struct device_attribute *attr,