Fix comment reference to variable name in header file.

git-svn-id: file:///svn/unbound/trunk@4838 be551aaa-1e26-0410-a405-d3ace91eadb9

Author: wcawijngaards

util/tcp_conn_limit.h

@@ -117,7 +117,7 @@ void tcl_close_connection(struct tcl_addr* tcl);
  * @return: tcl structure from this address.
  */
 struct tcl_addr*
-tcl_addr_lookup(struct tcl_list* acl, struct sockaddr_storage* addr,
+tcl_addr_lookup(struct tcl_list* tcl, struct sockaddr_storage* addr,
         socklen_t addrlen);
 
 /**