i965: Use new vtable entries for surface state updating functions.

i965: Use new vtable entries for surface state updating functions.

Now that we have vtable entries in place, we should use them.  This
allows us to drop the cut and pasted Gen7 brw_tracked_state atoms as
they now do exactly the same thing as their brw_wm_surface_state
counterparts.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Eric Anholt <eric@anholt.net>