[MTD] XIP: Use generic xip_iprefetch() instead of asm volatile (...)

Untested, but shouldn't break anything... Makes MTD_XIP arch
independent. I guess this is why xip_iprefetch() was made for.

Signed-off-by: Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
Acked-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
diff --git a/drivers/mtd/chips/cfi_probe.c b/drivers/mtd/chips/cfi_probe.c
index f651b6e..b03d43e 100644
--- a/drivers/mtd/chips/cfi_probe.c
+++ b/drivers/mtd/chips/cfi_probe.c
@@ -39,7 +39,7 @@
 #define xip_allowed(base, map) \
 do { \
 	(void) map_read(map, base); \
-	asm volatile (".rep 8; nop; .endr"); \
+	xip_iprefetch(); \
 	local_irq_enable(); \
 } while (0)