vnc: fix incorrect checking condition when updating client

vs->disconnecting is set to TRUE and vs->ioc is closed, but
vs->ioc isn't set to NULL, so that the vnc_disconnect_finish()
isn't invoked when you update client in vnc_update_client()
after vnc_disconnect_start invoked. Let's using change the checking
condition to avoid resource leak.

Signed-off-by: Haibin Wang <[email protected]>
Signed-off-by: Gonglei <[email protected]>
Reviewed-by: Daniel P. Berrange <[email protected]>
Message-id: [email protected]
Signed-off-by: Gerd Hoffmann <[email protected]>
(cherry picked from commit 5a693ef)
Signed-off-by: Michael Roth <[email protected]>

Author: gongleiarei

ui/vnc.c

@@ -1041,7 +1041,7 @@ static int vnc_update_client(VncState *vs, int has_dirty, bool sync)
     }
 
     vs->has_dirty += has_dirty;
-    if (vs->need_update && vs->ioc != NULL) {
+    if (vs->need_update && !vs->disconnecting) {
         VncDisplay *vd = vs->vd;
         VncJob *job;
         int y;