Always include <sys/cdefs.h> first.

Otherwise you can't be sure that things like __BIONIC__ work.

Change-Id: Ic5e59988b69419828c3b1a97332c7e2ab58e09a1
diff --git a/libc/include/arpa/nameser.h b/libc/include/arpa/nameser.h
index 97109ee..7f8b9ba 100644
--- a/libc/include/arpa/nameser.h
+++ b/libc/include/arpa/nameser.h
@@ -55,9 +55,10 @@
 
 #define BIND_4_COMPAT
 
-#include <sys/types.h>
 #include <sys/cdefs.h>
 
+#include <sys/types.h>
+
 /*
  * Revision information.  This is the release date in YYYYMMDD format.
  * It can change every day so the right thing to do with it is use it