Bump up ABI change

This covers the following changes.
https://aomedia.googlesource.com/aom/+log/v3.1.1-483-gd663fd976..v3.1.2-778-gf81be37aa/aom/aom_external_partition.h
Change-Id: I45c0b6936d635cb33dbf2f5c51a487411c68d83b
(cherry picked from commit 8e74697dc560781c46c23adce2dbcf091afe045f)
diff --git a/aom/aom_external_partition.h b/aom/aom_external_partition.h
index ad2214c..19c23cb 100644
--- a/aom/aom_external_partition.h
+++ b/aom/aom_external_partition.h
@@ -16,7 +16,7 @@
  *
  * @{
  */
-#include "./aom_integer.h"
+#include <stdint.h>
 
 /*!\file
  * \brief Provides function pointer definitions for the external partition.
@@ -30,7 +30,7 @@
  * types, removing or reassigning enums, adding/removing/rearranging
  * fields to structures.
  */
-#define AOM_EXT_PART_ABI_VERSION (2)
+#define AOM_EXT_PART_ABI_VERSION 3
 
 #ifdef __cplusplus
 extern "C" {