wined3d_context_vk_init() assumes zero-initialised memory, but that's not
necessarily true in case we previously went through an
adapter_vk_init_3d()/adapter_vk_uninit_3d() pair.
Signed-off-by: Henri Verbeet <hverbeet@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>