freemyip: Skip headers before processing response

This isn't strictly necessary but improves readability and
consistency.

ddclient.in

@@ -6424,7 +6424,8 @@ sub nic_freemyip_update {
             next;
         }
         next if !header_ok($h, $reply);
-        my @reply = split /\n/, $reply;
+        (my $body = $reply) =~ s/^.*?\n\n//s;
+        my @reply = split(/\n/, $body);
         my $returned = pop(@reply);
         if ($returned !~ /OK/) {
             failed("$h: Server said: $returned");