ffserver: do not ignore setsockopt return

Should fix FFmpeg Coverity Scan issue #732181
Signed-off-by: Reynaldo H. Verdejo Pinochet <r.verdejo@sisa.samsung.com>

ffserver.c

@@ -556,7 +556,8 @@ static int socket_open_listen(struct sockaddr_in *my_addr)
     }
 
     tmp = 1;
-    setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR, &tmp, sizeof(tmp));
+    if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR, &tmp, sizeof(tmp)))
+        av_log(NULL, AV_LOG_WARNING, "setsockopt SO_REUSEADDR failed\n");
 
     my_addr->sin_family = AF_INET;
     if (bind (server_fd, (struct sockaddr *) my_addr, sizeof (*my_addr)) < 0) {