Fbbootlogd doesn't do non-blocking operations, so fevent isn't needed.
And the kernel shouldn't pass closed handles to us and even if it does
due to a bug, it is harmless to silently ignore the fact that the handle
was closed.
While for now this for now only includes helpers for the current limited
display interface which is relatively simple to implement manually, in
the future we will likely need a more complex interface with gpu drivers
that would be hard to get right without a common crate proving the
interface.
The daemon responsible for the boot log must never ever block to avoid
deadlocks, but doing so while still accepting keyboard input is
non-trivial. This commit splits the boot log out from fbcond into a
separate daemon to make this a lot easier to implement. This will also
allow making fbcond blocking again, which will simplify some things.
bjorn3