hw/qxl: ignore guest from guestbug until reset

soft_reset is called from any of:
 * QXL_IO_RESET
 * vga io
 * pci reset handler

Signed-off-by: Alon Levy <alevy@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

hw/qxl.h

@@ -31,6 +31,9 @@ typedef struct PCIQXLDevice {
     uint32_t           debug;
     uint32_t           guestdebug;
     uint32_t           cmdlog;
+
+    uint32_t           guest_bug;
+
     enum qxl_mode      mode;
     uint32_t           cmdflags;
     int                generation;