vulkan/wsi: Provide the implicitly synchronized BO to vkQueueSubmit

vulkan/wsi: Provide the implicitly synchronized BO to vkQueueSubmit

This lets us treat the implicit synchronization that we need for X11 and
Wayland like a semaphore.  Instead of trusting the driver to somehow
figure out when that memory object needs to be signaled, we provide an
explicit point where the driver can set EXEC_OBJECT_WRITE and signal the
dma_fence on the BO.  Without this, we have to somehow track inside the
driver when WSI buffers are actually used to avoid extra synchronization
dependencies.

Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>