device/mmio.h: Add include file for MMIO ops

MMIO operations are arch-agnostic so the include
path should not be arch/.

Change-Id: I0fd70f5aeca02e98e96b980c3aca0819f5c44b98
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/31691
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/drivers/uart/oxpcie.c

@@ -19,7 +19,7 @@
 #include <device/pci_ids.h>
 #include <console/console.h>
 #include <console/uart.h>
-#include <arch/io.h>
+#include <device/mmio.h>
 #include <device/pci_ops.h>
 
 static void oxford_oxpcie_enable(struct device *dev)

src/drivers/uart/pl011.c

@@ -14,7 +14,7 @@
  * GNU General Public License for more details.
  */
 
-#include <arch/io.h>
+#include <device/mmio.h>
 #include <boot/coreboot_tables.h>
 #include <console/uart.h>
 #include <drivers/uart/pl011.h>

src/drivers/uart/sifive.c

@@ -13,7 +13,7 @@
  * GNU General Public License for more details.
  */
 
-#include <arch/io.h>
+#include <device/mmio.h>
 #include <boot/coreboot_tables.h>
 #include <console/uart.h>
 #include <types.h>

src/drivers/uart/uart8250mem.c

@@ -14,7 +14,7 @@
  * GNU General Public License for more details.
  */
 
-#include <arch/io.h>
+#include <device/mmio.h>
 #include <boot/coreboot_tables.h>
 #include <console/uart.h>
 #include <device/device.h>