systemd-logind integration does not work when starting X on a new tty, as
that detaches X from the current session and after hat systemd-logind revokes
all rights any already open fds and refuses to open new fds for X.
This means that currently e.g. "startx -- vt7" breaks, and breaks badly,
requiring ssh access to the system to kill X.
The fix for this is easy, we must not use systemd-logind integration when
not using KeepTty, or iow we may only use systemd-logind integration together
with KeepTty.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Tested-by: Aaron Plattner <aplattner@nvidia.com>