nv60: Add more or less correct cvt.
nv60: Add more or less correct cvt.

Like on tesla, this is an unholy mess. And there are yet more bits, sometimes...

hakzsam/envytools,kfractal/envytools,karolherbst/envytools,MoochMcGee/envytools,grate-driver/envytools,pierremoreau/envytools,envytools/envytools,hakzsam/envytools,grate-driver/envytools,hakzsam/envytools,kfractal/envytools,grate-driver/envytools,hakzsam/envytools,karolherbst/envytools,MoochMcGee/envytools,MoochMcGee/envytools,MoochMcGee/envytools,karolherbst/envytools,hakzsam/envytools,grate-driver/envytools,karolherbst/envytools,kfractal/envytools,karolherbst/envytools,MoochMcGee/envytools,grate-driver/envytools,pierremoreau/envytools,envytools/envytools,pierremoreau/envytools,envytools/envytools,pierremoreau/envytools,envytools/envytools,pierremoreau/envytools,envytools/envytools,kfractal/envytools,kfractal/envytools