Update fw/rs for Clang 3.5.

Change-Id: I0a9a1b1e61cb435f0102936ad9ffd51599c49e88

cpp/rsCppStructs.h

diff --git a/cpp/rsCppStructs.h b/cpp/rsCppStructs.h
index 8b07bf0..1ab1a6d 100644
--- a/cpp/rsCppStructs.h
+++ b/cpp/rsCppStructs.h
@@ -23,6 +23,7 @@
 
 #include <vector>
 #include <string>
+#include <pthread.h>
 
 /**
  * Every row in an RS allocation is guaranteed to be aligned by this amount, and