ide: ide_timing_compute() fixup

XFER_SW_DMA_0 mode should be excluded from the extended cycle
timing computations.

[ This is just a documentation fix -- code inside the affected
  'if' block already makes sure to accept only PIO modes. ]

Noticed-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/ide/ide-timings.c b/drivers/ide/ide-timings.c
index c7a65ee..0e05f75 100644
--- a/drivers/ide/ide-timings.c
+++ b/drivers/ide/ide-timings.c
@@ -166,7 +166,7 @@
 	if (id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE drive */
 		memset(&p, 0, sizeof(p));
 
-		if (speed >= XFER_PIO_0 && speed <= XFER_SW_DMA_0) {
+		if (speed >= XFER_PIO_0 && speed < XFER_SW_DMA_0) {
 			if (speed <= XFER_PIO_2)
 				p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO];
 			else if ((speed <= XFER_PIO_4) ||