ide: remove hwif->straight8 flag

All host drivers now either set hwif->mmio or reserve continuous
I/O resources so remove no longer needed hwif->straight8 flag
and never reached code for 'hwif->straight8 == 0' case.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

include/linux/ide.h

@@ -521,7 +521,6 @@ typedef struct hwif_s {
 	unsigned	reset      : 1;	/* reset after probe */
 	unsigned	sg_mapped  : 1;	/* sg_table and sg_nents are ready */
 	unsigned	mmio       : 1; /* host uses MMIO */
-	unsigned	straight8  : 1;	/* Alan's straight 8 check */
 
 	struct device		gendev;
 	struct device		*portdev;