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

Change-Id: I73c557d6ef009fb2cac35fdea500dee76f525330
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/32783
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>

src/mainboard/intel/baskingridge/chromeos.c

@@ -15,7 +15,6 @@
 
 #include <string.h>
 #include <bootmode.h>
-#include <arch/io.h>
 #include <device/pci_ops.h>
 #include <device/device.h>
 #include <device/pci.h>