feat(host): forwarder: add NewClient func

pkg/hostman/guestman/forwarder/client.go

@@ -0,0 +1,18 @@
+package forwarder
+
+import (
+	"google.golang.org/grpc"
+
+	"yunion.io/x/pkg/errors"
+
+	pb "yunion.io/x/onecloud/pkg/hostman/guestman/forwarder/api"
+)
+
+func NewClient(target string) (pb.ForwarderClient, error) {
+	cc, err := grpc.Dial(target, grpc.WithInsecure())
+	if err != nil {
+		return nil, errors.Wrap(err, "grpc Dial")
+	}
+	c := pb.NewForwarderClient(cc)
+	return c, nil
+}