[master] adding missing header file to include (sys/types for sys/socket)

build on openbsd fails without this.
should be trivial, so commiting this at my discretion.

src/lib/util/io/sockaddr_util.h

@@ -15,6 +15,7 @@
 #ifndef __SOCKADDR_UTIL_H_
 #define __SOCKADDR_UTIL_H_ 1
 
+#include <sys/types.h>
 #include <sys/socket.h>
 #include <netinet/in.h>