Replace the deprecated grpclog.Printf with grpclog.Infof

grpclog.Printf is marked as deprecated, which causes code linting tools
like https://github.com/dominikh/go-tools/tree/master/staticcheck to
flag the go files generated by this tool:
https://godoc.org/google.golang.org/grpc/grpclog#Printf

protoc-gen-grpc-gateway/gengateway/template.go

@@ -157,7 +157,7 @@ func request_{{.Method.Service.GetName}}_{{.Method.GetName}}_{{.Index}}(ctx cont
 	var metadata runtime.ServerMetadata
 	stream, err := client.{{.Method.GetName}}(ctx)
 	if err != nil {
-		grpclog.Printf("Failed to start streaming: %v", err)
+		grpclog.Infof("Failed to start streaming: %v", err)
 		return nil, metadata, err
 	}
 	dec := marshaler.NewDecoder(req.Body)
@@ -168,22 +168,22 @@ func request_{{.Method.Service.GetName}}_{{.Method.GetName}}_{{.Index}}(ctx cont
 			break
 		}
 		if err != nil {
-			grpclog.Printf("Failed to decode request: %v", err)
+			grpclog.Infof("Failed to decode request: %v", err)
 			return nil, metadata, status.Errorf(codes.InvalidArgument, "%v", err)
 		}
 		if err = stream.Send(&protoReq); err != nil {
-			grpclog.Printf("Failed to send request: %v", err)
+			grpclog.Infof("Failed to send request: %v", err)
 			return nil, metadata, err
 		}
 	}
 
 	if err := stream.CloseSend(); err != nil {
-		grpclog.Printf("Failed to terminate client stream: %v", err)
+		grpclog.Infof("Failed to terminate client stream: %v", err)
 		return nil, metadata, err
 	}
 	header, err := stream.Header()
 	if err != nil {
-		grpclog.Printf("Failed to get header from client: %v", err)
+		grpclog.Infof("Failed to get header from client: %v", err)
 		return nil, metadata, err
 	}
 	metadata.HeaderMD = header
@@ -260,7 +260,7 @@ var (
 	var metadata runtime.ServerMetadata
 	stream, err := client.{{.Method.GetName}}(ctx)
 	if err != nil {
-		grpclog.Printf("Failed to start streaming: %v", err)
+		grpclog.Infof("Failed to start streaming: %v", err)
 		return nil, metadata, err
 	}
 	dec := marshaler.NewDecoder(req.Body)
@@ -271,18 +271,18 @@ var (
 			return err
 		}
 		if err != nil {
-			grpclog.Printf("Failed to decode request: %v", err)
+			grpclog.Infof("Failed to decode request: %v", err)
 			return err
 		}
 		if err := stream.Send(&protoReq); err != nil {
-			grpclog.Printf("Failed to send request: %v", err)
+			grpclog.Infof("Failed to send request: %v", err)
 			return err
 		}
 		return nil
 	}
 	if err := handleSend(); err != nil {
 		if cerr := stream.CloseSend(); cerr != nil {
-			grpclog.Printf("Failed to terminate client stream: %v", cerr)
+			grpclog.Infof("Failed to terminate client stream: %v", cerr)
 		}
 		if err == io.EOF {
 			return stream, metadata, nil
@@ -296,12 +296,12 @@ var (
 			}
 		}
 		if err := stream.CloseSend(); err != nil {
-			grpclog.Printf("Failed to terminate client stream: %v", err)
+			grpclog.Infof("Failed to terminate client stream: %v", err)
 		}
 	}()
 	header, err := stream.Header()
 	if err != nil {
-		grpclog.Printf("Failed to get header from client: %v", err)
+		grpclog.Infof("Failed to get header from client: %v", err)
 		return nil, metadata, err
 	}
 	metadata.HeaderMD = header
@@ -322,14 +322,14 @@ func Register{{$svc.GetName}}HandlerFromEndpoint(ctx context.Context, mux *runti
 	defer func() {
 		if err != nil {
 			if cerr := conn.Close(); cerr != nil {
-				grpclog.Printf("Failed to close conn to %s: %v", endpoint, cerr)
+				grpclog.Infof("Failed to close conn to %s: %v", endpoint, cerr)
 			}
 			return
 		}
 		go func() {
 			<-ctx.Done()
 			if cerr := conn.Close(); cerr != nil {
-				grpclog.Printf("Failed to close conn to %s: %v", endpoint, cerr)
+				grpclog.Infof("Failed to close conn to %s: %v", endpoint, cerr)
 			}
 		}()
 	}()

runtime/context.go

@@ -80,7 +80,7 @@ func AnnotateContext(ctx context.Context, mux *ServeMux, req *http.Request) (con
 				pairs = append(pairs, strings.ToLower(xForwardedFor), fmt.Sprintf("%s, %s", fwd, remoteIP))
 			}
 		} else {
-			grpclog.Printf("invalid remote addr: %s", addr)
+			grpclog.Infof("invalid remote addr: %s", addr)
 		}
 	}