tools: use standard interpreter path in all Perl scripts

Signed-off-by: David Ward <david.ward@ll.mit.edu>
[changed /usr/bin/perl to /usr/bin/env perl]
Signed-off-by: David Lamparter <equinox@diac24.net>

tools/rrcheck.pl

@@ -1,4 +1,4 @@
-#! /bin/perl
+#!/usr/bin/env perl
 ##
 ## Read BGPd logfile and lookup RR's whois database.
 ##

tools/rrlookup.pl

@@ -1,4 +1,4 @@
-#! /usr/local/bin/perl
+#!/usr/bin/env perl
 ##
 ## Read BGPd logfile and lookup RR's whois database.
 ##

tools/zc.pl

@@ -1,4 +1,4 @@
-#! /usr/bin/perl
+#!/usr/bin/env perl
 ##
 ## Zebra interactive console
 ## Copyright (C) 2000 Vladimir B. Grebenschikov <vova@express.ru>