Well, we need a new key if we don't havre one, not if we already have one

Signed-off-by: Florian Aders <eleras@froxlor.org>

lib/classes/ssl/class.lescript.php

@@ -182,7 +182,7 @@ class lescript
         // ----------------------
 
         // generate private key for domain if not exist
-        if(!is_null($domainkey)) {
+        if(empty($domainkey)) {
             $keys = $this->generateKey();
             $domainkey = $keys['private'];
         }