The TFU lets us format raster and SAND images into formats that can be
read by the texture engine, and do mipmap generation.
The UAPI comes from drm-next e69aa5f9b97f ("Merge tag
'drm-misc-next-2018-12-06' of git://anongit.freedesktop.org/drm/drm-misc
into drm-next")
In the process of merging to the kernel, I renamed the driver to the
general product line's name (since we have both vc5 and vc6 supported
already). Since the ABI is finalized, move the header to include/drm-uapi.