logind: fix closing of button input devices
This is a fix of #17751. Specifically:
1. Sort #include headers again
2. Remove tabs, as per coding style
3. Don't install fds in half-initialized objects
4. Use asynchronous_close() everywhere
That all said:
Quit frankly, I am not convinced we should do all this at all. If
close()ing of these input devices is really that slow, then this should
probably be fixed in the kernel, not worked around in userspace like
this.
(cherry picked from commit
c74d5fe25d53263c143f0a9c2698d8bb483e398c)