i965g: clean up inline write again
i965g: improve transfer_map()
i965g: has_llc is wrongly set to false on gen6+
i965g: update comments on bo mapping
i965g: prefer map() over map_gtt() when there is LLC
i965g: minor i965_resource clean-ups
i965g: clean up how tiling is chosen

And prefer Y over X.
i965g: clean up layout_tex_2d()
i965g: clean up layout_tex_3d()
i965g: clean up layout_tex_init()