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/memmap.c b/src/northbridge/intel/sandybridge/memmap.c
index 8da4ec9..b0a5149 100644
--- a/src/northbridge/intel/sandybridge/memmap.c
+++ b/src/northbridge/intel/sandybridge/memmap.c
@@ -10,6 +10,8 @@
 #include <cpu/x86/smm.h>
 #include <program_loading.h>
 #include "sandybridge.h"
+#include <stddef.h>
+#include <stdint.h>
 
 static uintptr_t smm_region_start(void)
 {