vulkan/wsi/wayland: Use proxy wrappers for swapchain

vulkan/wsi/wayland: Use proxy wrappers for swapchain

Though most swapchain operations used a queue, they were racy in that
the object was created with the queue only set later, meaning that its
event could potentially be dispatched from the default queue in between
these two steps.

Use proxy wrappers to avoid this race, also assigning wl_buffers created
for the swapchain to the event queue.

Signed-off-by: Daniel Stone <daniels@collabora.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: mesa-stable@lists.freedesktop.org