Fix build failure due to missing include of udp.h #351602

Patch by Kevin McCarthy <signals@gentoo.org>

--- rtpbreak-1.3a.orig/src/main.c	2011-01-29 11:10:46.960653580 -0500
+++ rtpbreak-1.3a/src/main.c	2011-01-29 11:15:15.833884433 -0500
@@ -27,6 +27,7 @@
 #include <sys/stat.h>
 #include <pwd.h>
 #include <grp.h>
+#include <netinet/udp.h>
 #include "queue.h"
 #include "rtp.h"
 #include "common.h"