deregister options needed for exploitation

Author: jvazquez-r7

modules/exploits/unix/dhcp/bash_environment.rb

@@ -51,7 +51,7 @@ def initialize(info = {})
       'DisclosureDate' => 'Sep 24 2014'
     ))
 
-    deregister_options('DOMAINNAME')
+    deregister_options('DOMAINNAME', 'HOSTNAME', 'URL')
   end
 
   def on_new_session(session)