nb/intel/sandybridge: Add missing includes

Change-Id: I9d54d0923a595734a84256ddcafb9dae17615cb0
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/43348
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/northbridge/intel/sandybridge/common.c b/src/northbridge/intel/sandybridge/common.c
index b27911d..5cd49cc 100644
--- a/src/northbridge/intel/sandybridge/common.c
+++ b/src/northbridge/intel/sandybridge/common.c
@@ -2,6 +2,7 @@
 
 #include <console/console.h>
 #include <device/device.h>
+#include <cpu/intel/model_206ax/model_206ax.h>
 #include "sandybridge.h"
 
 enum platform_type get_platform_type(void)