remove double check for emtpy sshkey

signup/signup-handler.php

@@ -150,7 +150,7 @@ if (isset($_REQUEST["username"]) && isset($_REQUEST["email"])) {
             . 'see our <a href="https://tilde.team/wiki/?page=ssh">ssh wiki</a> or '
             . 'hop on <a href="https://web.tilde.chat/?join=team">irc</a> and ask for help</li>';
     else {
-        if ($sshkey != "" && forbidden_sshkey($sshkey)) {
+        if (forbidden_sshkey($sshkey)) {
             $message .= "<li>your sshkey is banned!</li>\n";
             add_ban_info($name, $email);
         }