core: Fix misleading log message in ProviderTransformer

The final "<resource> provided by <provider>" message was showing the
original selection made by the resource itself rather than the provider
address finally resolved after inheritance, which caused the log to
misrepresent what was actually being created in the graph.

terraform/transform_provider.go

@@ -130,7 +130,7 @@ func (t *ProviderTransformer) Transform(g *Graph) error {
 				key = target.(GraphNodeProvider).ProviderAddr().String()
 			}
 
-			log.Printf("[DEBUG] %s provided by %s", dag.VertexName(pv), key)
+			log.Printf("[DEBUG] %s provided by %s", dag.VertexName(pv), dag.VertexName(target))
 			pv.SetProvider(target.ProviderAddr())
 			g.Connect(dag.BasicEdge(v, target))
 		}