additional includes needed for MIPS toolchain after move of hashmap

Follow up from https://codereview.chromium.org/2010243003

BUG=v8:5050

Review-Url: https://codereview.chromium.org/2071273003
Cr-Commit-Position: refs/heads/master@{#37103}

src/base/hashmap.h

@@ -9,6 +9,8 @@
 #ifndef V8_BASE_HASHMAP_H_
 #define V8_BASE_HASHMAP_H_
 
+#include <stdlib.h>
+
 #include "src/base/bits.h"
 #include "src/base/logging.h"
 

src/profiler/strings-storage.h

@@ -5,6 +5,8 @@
 #ifndef V8_PROFILER_STRINGS_STORAGE_H_
 #define V8_PROFILER_STRINGS_STORAGE_H_
 
+#include <stdarg.h>
+
 #include "src/allocation.h"
 #include "src/base/compiler-specific.h"
 #include "src/base/hashmap.h"