The Vulkan spec says:

  "When a pool is destroyed, all command buffers allocated from the pool
  are implicitly freed and become invalid. Command buffers allocated
  from a given pool do not need to be freed before destroying that
  command pool."
Signed-off-by: Józef Kucia <jkucia@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>