Revert the change in VA_DRI2SwapBuffers: _XReply -->_XSend

We should use _XReplay. _XSend will introduce more CPU usage
Signed-off-by: Edgar Hucek <gimli@dark-green.com>
Signed-off-by: Austin Yuan <shengquan.yuan@gmail.com>

va/x11/va_dri2.c

@@ -340,9 +340,9 @@ void VA_DRI2SwapBuffers(Display *dpy, XID drawable, CARD64 target_msc,
     req->drawable = drawable;
     load_swap_req(req, target_msc, divisor, remainder);
 
-    _XSend(dpy, NULL, 0);
+    _XReply(dpy, (xReply *)&rep, 0, xFalse);
 
-    *count = 0;
+    *count = vals_to_card64(rep.swap_lo, rep.swap_hi);
 
     UnlockDisplay(dpy);
     SyncHandle();