Make iptables-restore usable over a pipe

The attached patch flushes stdout between commands to make output
operations (-L etc) in iptables-restore usable over a pipe. stdio by
defaut buffers output if not connected to a terminal.

Henrik Nordstrom <henrik@henriknordstrom.net>
diff --git a/iptables-restore.c b/iptables-restore.c
index ee3ba45..879683c 100644
--- a/iptables-restore.c
+++ b/iptables-restore.c
@@ -442,6 +442,7 @@
 					 &newargv[2], &handle);
 
 			free_argv();
+			fflush(stdout);
 		}
 		if (tablename && (strcmp(tablename, curtable) != 0))
 			continue;