nvhw/xf: Fix alpha passthru with light material diffuse.
nvhw/xf: Fix alpha passthru with light material diffuse.

pierremoreau/envytools,envytools/envytools,pierremoreau/envytools,envytools/envytools,pierremoreau/envytools,karolherbst/envytools,envytools/envytools,karolherbst/envytools,envytools/envytools,pierremoreau/envytools,karolherbst/envytools,envytools/envytools,pierremoreau/envytools,karolherbst/envytools,karolherbst/envytools