src/northbridge: Remove unneeded include <arch/io.h>

Change-Id: I52ace93ae6f802723823955ac349ed54dc064aaa
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/32784
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>

src/northbridge/intel/sandybridge/raminit.c

@@ -21,7 +21,6 @@
 #include <cf9_reset.h>
 #include <string.h>
 #include <arch/cpu.h>
-#include <arch/io.h>
 #include <device/mmio.h>
 #include <device/pci_ops.h>
 #include <cbmem.h>