fix: [lnfs] maintain two mounting methods for long file names

[pppanghu77]

It can be mounted through both ULNFS and DLNFS

Log: [lnfs] maintain two mounting methods for long file names
Task: https://pms.uniontech.com/task-view-359649.html

[deepin-ci-robot]

deepin pr auto review

关键摘要:

• 代码中存在重复的代码片段，例如在处理ulnfs和dlnfs的脚本中存在相似的逻辑。建议将这些重复的代码片段抽象成函数以提高代码的可维护性。
• 在处理ulnfs和dlnfs的脚本中，对环境变量的处理逻辑不一致，可能导致在不同环境下行为不一致的问题。
• 脚本中使用了硬编码的字符串，建议将这些字符串定义为常量或配置项，以便于管理和修改。
• 脚本中的错误处理不完善，例如在执行gdbus call命令时，如果脚本执行失败，没有相应的错误处理逻辑。
• 脚本中的日志输出使用了echo命令，建议使用日志库来记录日志，以便于统一管理和控制日志的输出。

是否建议立即修改:
是

[deepin-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: max-lvs, pppanghu77

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[pppanghu77]

/merge