ide: remove "idex=dma" kernel parameter

It has been obsoleted since 1 Nov 2004, is valid only when used together with
"ide=nodma" kernel parameter (which makes no sense) and only for aec62xx,
cmd64x, cs5220, generic, hpt366, sl82c105, tc86c001 and triflex host drivers.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Documentation/ide.txt

@@ -278,8 +278,6 @@ Summary of ide driver parameters for kernel command line
  "idex=four"		: four drives on idex and ide(x^1) share same ports
 			
  "idex=reset"		: reset interface after probe
- 
- "idex=dma"		: automatically configure/use DMA if possible.
 
  "idex=ata66"		: informs the interface that it has an 80c cable
 			  for chipsets that are ATA-66 capable, but the

drivers/ide/ide.c

@@ -1396,7 +1396,7 @@ static int __init ide_setup(char *s)
 		 */
 		static const char *ide_words[] = {
 			"noprobe", "serialize", "minus3", "minus4",
-			"reset", "dma", "ata66", "minus8", "minus9",
+			"reset", "minus6", "ata66", "minus8", "minus9",
 			"minus10", "four", "qd65xx", "ht6560b", "cmd640_vlb",
 			"dtc2278", "umc8672", "ali14xx", NULL };
 		hw = s[3] - '0';
@@ -1475,6 +1475,7 @@ static int __init ide_setup(char *s)
 			case -10: /* minus10 */
 			case -9: /* minus9 */
 			case -8: /* minus8 */
+			case -6:
 			case -4:
 			case -3:
 				goto bad_option;
@@ -1489,9 +1490,6 @@ static int __init ide_setup(char *s)
 #else
 				goto bad_hwif;
 #endif
-			case -6: /* dma */
-				hwif->autodma = 1;
-				goto obsolete_option;
 			case -5: /* "reset" */
 				hwif->reset = 1;
 				goto obsolete_option;