[InitSystem] Allow toggle of default `is_running` result

The base `InitSystem` used when systemd is not present (or at least
functional), defaults to returning `True` for all probes, in an effort
to not inadvertantly block service queries.

This works well for most scenarios, however it backfires when checking
for runlevel-analogous systemd targets for items such as the `cantboot`
preset - in that the base `InitSystem` will always enable that preset.

Fix that by allowing calls to `InitSystem.is_running()` to specify a
default value to return, instead of blindly always returning `True`.
Similarly, update the preset check to default to `False` to avoid
improperly enabling that preset when systemd is unavailable.

Closes: #2913

Signed-off-by: Jake Hunsaker <jhunsake@redhat.com>

0 files changed, 0 insertions, 0 deletions