unix-manager: fix memleak at exit

Buffer allocated for UnixClient was not correctly freed.

src/unix-manager.c

@@ -580,6 +580,9 @@ int UnixMain(UnixCommand * this)
     }
 
     if (suricata_ctl_flags & (SURICATA_STOP | SURICATA_KILL)) {
+        TAILQ_FOREACH_SAFE(uclient, &this->clients, next, tclient) {
+            UnixCommandClose(this, uclient->fd);
+        }
         return 1;
     }