[qpid-dispatch] Crash when trying to close a NULL listener

[Adel Boutros]

Hello,
In qpid-dispatch, we have a core dump and a segmentation fault when a 
qd_listener_t is being closed but it is NULL:
src/server.c:1614
void qd_server_listener_close(qd_listener_t* li){       
qdpn_listener_close(li->pn_listener);







}
A check on li would fix this crash.
Fix:void qd_server_listener_close(qd_listener_t* li){    if
(li)       qdpn_listener_close(li->pn_listener);







}
Regards,Adel