ide: remove redundant ->ide_dma_on call from set_using_dma()

ide_set_dma() calls ->ide_dma_on method itself and returns zero
only if ->ide_dma_on call succeeded.

There should be no functionality changes caused by this patch.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/ide/ide.c

@@ -852,7 +852,7 @@ int set_using_dma(ide_drive_t *drive, int arg)
 
 	if (arg) {
 		hwif->dma_off_quietly(drive);
-		if (ide_set_dma(drive) || hwif->ide_dma_on(drive))
+		if (ide_set_dma(drive))
 			err = -EIO;
 	} else
 		ide_dma_off(drive);