sql: don't make a redundant copy of the SetupFlowRequest for local flow

We can just use the setup request directly since all remote requests (if
any) did make copies of the original request.

Release note: None

pkg/sql/distsql_running.go

@@ -356,15 +356,14 @@ func (dsp *DistSQLPlanner) setupFlows(
 	}
 
 	// Set up the flow on this node.
-	localReq := setupReq
-	localReq.Flow = *flows[thisNodeID]
+	setupReq.Flow = *flows[thisNodeID]
 	var batchReceiver execinfra.BatchReceiver
 	if recv.batchWriter != nil {
 		// Use the DistSQLReceiver as an execinfra.BatchReceiver only if the
 		// former has the corresponding writer set.
 		batchReceiver = recv
 	}
-	return dsp.distSQLSrv.SetupLocalSyncFlow(ctx, evalCtx.Mon, &localReq, recv, batchReceiver, localState)
+	return dsp.distSQLSrv.SetupLocalSyncFlow(ctx, evalCtx.Mon, &setupReq, recv, batchReceiver, localState)
 }
 
 // Run executes a physical plan. The plan should have been finalized using