Cleanup includes for rs/cpp to not expose internal details.

Change-Id: Ib23f591f8418d3318f61ab1d3f6f2b684bf95692
diff --git a/cpp/RenderScript.cpp b/cpp/RenderScript.cpp
index e2fd651..4474741 100644
--- a/cpp/RenderScript.cpp
+++ b/cpp/RenderScript.cpp
@@ -21,6 +21,7 @@
 #include "RenderScript.h"
 #include "rsCppStructs.h"
 #include "rsCppInternal.h"
+#include "rsDispatch.h"
 
 #include <dlfcn.h>
 #include <unistd.h>