wip/elogind 246.10 NetBSD

Elogind is the systemd project's "logind", extracted out to be a standalone daemon. It integrates with PAM to know the set of users that are logged in to a system and whether they are logged in graphically, on the console, or remotely. Elogind exposes this information via the standard org.freedesktop.login1 D-Bus interface, as well as through the file system using systemd's standard /run/systemd layout. Elogind also provides "libelogind", which is a subset of the facilities offered by "libsystemd". There is a "libelogind.pc" pkg-config file as well.