anv: Fix wait_count missing increment

If we don't wait on anything, I bet it makes the QueuePresent faster, but also completely wrong...

Signed-off-by: Lionel Landwerlin lionel.g.landwerlin@intel.com Fixes: 49ad5b2d ("anv: don't wait for completion of work on vkQueuePresent()") Closes: #4276 (closed)