MarkDeprecated and NormalizeFunc as alias results in an inconsistent deprecation message

[andersjanmyr]

cmd.Flags().StringVar(&src, "dir", "", "deprecated, use src")
cmd.Flags().MarkDeprecated("dir", "dir has been renamed src")
cmd.Flags().StringVar(&src, "src", "", "src directory or file")
cmd.Flags().SetNormalizeFunc(aliasNormalizeFunc)

$ go run . --dir=test
Flag --src has been deprecated, dir has been renamed src