[Mesa-dev] r600 sb tessellation support

[Dave Airlie]

This is an attempt to add tessellation support to the SB backend.

The main things needed are GDS access which is used for tess
factor storage (also used for atomic counters), and LDS access
which is needed to pass all the data between stages.

The first 19 patches are the stuff I'm happy with, the
nop/sanity shader tests pass with those (and sb enabled).

The last two patches make heaven work and turn on sb,
I'm not suggested these be applied as-is yet.

I think in theory enabling sb for atomics/images/compute should
be fine after this series as well, but I haven't tested that too
much.