lastlog2 is the 2038-safe replacement for wtmp, and in the meantime
became part of util-linux.
This commit switches from trying to parse the lastlog2 output to
directly reading lastlog2.db with sqlite3.
Adjust get_last_login_timestamp() to use the lastlog2 database
(/var/lib/lastlog/lastlog2.db) if it exists, and adjust
get_last_login_timestamp_lastlog2() to actually do that.
(If lastlog2.db doesn't exist, aa-notify will read wtmp as usual.)
Unfortunately lastlog2 doesn't have a way to get machine-readable output
(for example json), therefore - after trying and failing to parse the
lastlog2 output - directly read from lastlog2.db. Let's hope the format
never changes ;-)
Fixes: https://bugzilla.opensuse.org/show_bug.cgi?id=1228378
Fixes: https://bugzilla.opensuse.org/show_bug.cgi?id=1216660
Fixes: https://gitlab.com/apparmor/apparmor/-/issues/372
Both aarch64 and s390x have a bigger wtmp record size (16 bytes more
than x86_64, 400 bytes total).
The byte position of the timestamp is also different on each
architecture. To make things even more interesting, s390x is big endian.
Fixes: https://bugzilla.opensuse.org/show_bug.cgi?id=1181155
