Move spec generation to Container Create

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

cmd/ctr/run_unix.go

@@ -111,11 +111,7 @@ func newContainer(ctx gocontext.Context, client *containerd.Client, context *cli
 	if context.Bool("net-host") {
 		opts = append(opts, setHostNetworking())
 	}
-	spec, err := containerd.GenerateSpec(ctx, client, opts...)
-	if err != nil {
-		return nil, err
-	}
-	cOpts = append([]containerd.NewContainerOpts{containerd.WithSpec(spec)}, cOpts...)
+	cOpts = append([]containerd.NewContainerOpts{containerd.WithNewSpec(opts...)}, cOpts...)
 	return client.NewContainer(ctx, id, cOpts...)
 }