vnc: keep track of client desktop size

Add two new variables to keep track of the vnc clients desktop size.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/vnc.h b/vnc.h
index 51595e6..7b64cf7 100644
--- a/vnc.h
+++ b/vnc.h
@@ -134,6 +134,8 @@
     int absolute;
     int last_x;
     int last_y;
+    int client_width;
+    int client_height;
 
     uint32_t vnc_encoding;