Revert "Disable `docker system dial-stdio` on Windows"

This reverts commit c41c23813c.

This case is now handled due to the previous commit.

Signed-off-by: Ian Campbell <ijc@docker.com>

cli-plugins/plugin/plugin.go

@@ -4,7 +4,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"os"
-	"runtime"
 	"sync"
 
 	"github.com/docker/cli/cli"
@@ -75,11 +74,7 @@ func PersistentPreRunE(cmd *cobra.Command, args []string) error {
 		}
 		// flags must be the original top-level command flags, not cmd.Flags()
 		options.opts.Common.SetDefaultOptions(options.flags)
-		var initopts []command.InitializeOpt
+		err = options.dockerCli.Initialize(options.opts, withPluginClientConn(options.name))
-		if runtime.GOOS != "windows" {
-			initopts = append(initopts, withPluginClientConn(options.name))
-		}
-		err = options.dockerCli.Initialize(options.opts, initopts...)
 	})
 	return err
 }

cli/command/system/cmd.go

@@ -1,8 +1,6 @@
 package system
 
 import (
-	"runtime"
-
 	"github.com/docker/cli/cli"
 	"github.com/docker/cli/cli/command"
 	"github.com/spf13/cobra"
@@ -21,12 +19,8 @@ func NewSystemCommand(dockerCli command.Cli) *cobra.Command {
 		NewInfoCommand(dockerCli),
 		newDiskUsageCommand(dockerCli),
 		newPruneCommand(dockerCli),
+		newDialStdioCommand(dockerCli),
 	)
-	if runtime.GOOS != "windows" {
-		cmd.AddCommand(
-			newDialStdioCommand(dockerCli),
-		)
-	}
 
 	return cmd
 }