[MTD] XIP cleanup

Move the architecture dependend code into include/asm/mtd-xip.h

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/drivers/mtd/chips/cfi_cmdset_0001.c b/drivers/mtd/chips/cfi_cmdset_0001.c
index 8b13045..0cfcd88 100644
--- a/drivers/mtd/chips/cfi_cmdset_0001.c
+++ b/drivers/mtd/chips/cfi_cmdset_0001.c
@@ -845,7 +845,7 @@
 		chip->state = FL_READY;
 	}
 	(void) map_read(map, adr);
-	asm volatile (".rep 8; nop; .endr"); /* fill instruction prefetch */
+	xip_iprefetch();
 	local_irq_enable();
 }