[tracing] Simplify include statement.

Change include statement, otherwise embedders have problems compiling.

BUG=

Review-Url: https://codereview.chromium.org/2378773004
Cr-Commit-Position: refs/heads/master@{#39850}

include/libplatform/v8-tracing.h

@@ -10,7 +10,7 @@
 #include <unordered_set>
 #include <vector>
 
-#include "include/v8-platform.h"
+#include "v8-platform.h"  // NOLINT(build/include)
 
 namespace v8 {