Fix BSD compile (PF_UNSPEC is not a standard define, AF_UNSPEC is).

Originally committed as revision 21490 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/tcp.c

@@ -53,7 +53,7 @@ static int tcp_open(URLContext *h, const char *uri, int flags)
         return AVERROR(EINVAL);
 
     memset(&hints, 0, sizeof(hints));
-    hints.ai_family = PF_UNSPEC;
+    hints.ai_family = AF_UNSPEC;
     hints.ai_socktype = SOCK_STREAM;
     snprintf(portstr, sizeof(portstr), "%d", port);
     if (getaddrinfo(hostname, portstr, &hints, &ai))