radeonsi/gfx10: correct VS PrimitiveID implementation for NGG

We didn't use the correct LDS pointer, though it probably doesn't matter,
because I think that nothing else is using LDS here.

This commit makes it consistent with all other esgs_ring use.

Acked-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
1 file changed