ide: remove obsoleted "hdx=autotune" kernel parameter

* Remove obsoleted "hdx=autotune" kernel parameter
  (we always auto-tune PIO if possible nowadays).

* Remove no longer needed ide_drive_t.autotune flag.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ide.c b/drivers/ide/ide.c
index ad34fe9..71fa379 100644
--- a/drivers/ide/ide.c
+++ b/drivers/ide/ide.c
@@ -900,7 +900,7 @@
 	if (s[0] == 'h' && s[1] == 'd' && s[2] >= 'a' && s[2] <= max_drive) {
 		const char *hd_words[] = {
 			"none", "noprobe", "nowerr", "cdrom", "nodma",
-			"autotune", "-7", "-8", "-9", "-10",
+			"-6", "-7", "-8", "-9", "-10",
 			"noflush", "remap", "remap63", "scsi", NULL };
 		unit = s[2] - 'a';
 		hw   = unit / MAX_DRIVES;
@@ -928,9 +928,6 @@
 			case -5: /* nodma */
 				drive->nodma = 1;
 				goto done;
-			case -6: /* "autotune" */
-				drive->autotune = 1;
-				goto obsolete_option;
 			case -11: /* noflush */
 				drive->noflush = 1;
 				goto done;