demo: Remove total_triangles computation

It's mostly not meaningful other than as a rough sense of the overall
memory consumption.

Author: zeux

demo/nanite.cpp

@@ -386,16 +386,11 @@ void nanite(const std::vector<Vertex>& vertices, const std::vector<unsigned int>
 		}
 	}
 
-	size_t total_triangles = 0;
 	size_t lowest_triangles = 0;
 	for (size_t i = 0; i < clusters.size(); ++i)
-	{
-		total_triangles += clusters[i].indices.size() / 3;
 		if (clusters[i].parent.error == FLT_MAX)
 			lowest_triangles += clusters[i].indices.size() / 3;
-	}
 
-	printf("total: %d triangles in %d clusters\n", int(total_triangles), int(clusters.size()));
 	printf("lowest lod: %d triangles\n", int(lowest_triangles));
 
 	// for testing purposes, we can compute a DAG cut from a given viewpoint and dump it as an OBJ