Attempt to fix 'mutex.h' not found when building mutex_posix.
am: b682df64d3

Change-Id: I48f23110dccc50697aaeb1a153ec49aa76b74c5c
diff --git a/gwp_asan/platform_specific/mutex_posix.cpp b/gwp_asan/platform_specific/mutex_posix.cpp
index e15bca8..8bd405e 100644
--- a/gwp_asan/platform_specific/mutex_posix.cpp
+++ b/gwp_asan/platform_specific/mutex_posix.cpp
@@ -6,7 +6,7 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "mutex.h"
+#include "gwp_asan/mutex.h"
 
 #include <assert.h>
 #include <pthread.h>