Battery monitor settings disabled only on first run

[stefonarch]

At first login on a machine without battery a info is displayed: "Could not find any battery, battery monitor disabled" and it works.

But when checking later the corresponding box in lxqt-config-powermanagement the same message will show up immediately, but the checkbox will remain checked. At next login the same message will be showed again, until the user manually disables it.

Expected Behavior

According to the message, it should be disabled in the setting.

Current Behavior

It is always active

Possible Solution

Do not show any battery or lid related setting (or only greyed out) when no lid and/or no battery is present, as in https://github.com/lxqt/lxqt-powermanagement/issues/261

Steps to Reproduce (for bugs)

1. On a PC Desktop or in Virtualbox activate battery monitor.
2. A message will be displayed, saying it will be disabled.
3. Control the settings, still active
4. Restart session, again the message and no result.

System Information

• Distribution & Version: latest git, all prior versions probably