Fix regex to match format of iptables-save from iptables >= 1.4.15

cleanup_rules.awk optimizes the set of rules from iptables-save output.
In iptables < 1.4.15 the lines with these rules contains a trailing space,
in iptables >= 1.4.15 that trailing space is ommited.

--- src/cleanup_rules.awk
+++ src/cleanup_rules.awk
@@ -43,11 +43,11 @@ function scan_rule(string,
         chain = substr(string, RSTART, RLENGTH);
 	spec_start = RLENGTH+2;
 
-        if ( match(string, "-j[ ][a-zA-Z0-9_+]+.*") == 0) {
+        if ( match(string, "-j[ ][a-zA-Z0-9_+]+.*[^ ]") == 0) {
 	    printf("Rule with no target: -A %s %s\n", chain, specification);
 	    return;
 	}
-	target = substr(string, RSTART+3, RLENGTH-4);
+	target = substr(string, RSTART+3, RLENGTH-3);
 	specification = substr(string, spec_start, length(string) - spec_start - (RLENGTH));
 
 	if ( specification == "" && target == "" ) {