Fix iptables-save not printing -s !0/0 and -d !0/0 as well as ip6tables
unnecessarily printing the address. Base on patch by Daniel De Graaf.
diff --git a/iptables-save.c b/iptables-save.c
index 79b5dc7..ee18918 100644
--- a/iptables-save.c
+++ b/iptables-save.c
@@ -141,7 +141,7 @@
 /* print a given ip including mask if neccessary */
 static void print_ip(char *prefix, u_int32_t ip, u_int32_t mask, int invert)
 {
-	if (!mask && !ip)
+	if (!mask && !ip && !invert)
 		return;
 
 	printf("%s %s%u.%u.%u.%u",