Remove ulog_check(); the ulog is not a DB journal

The db2 DB is not power-fail safe.  There's no point trying to
replay an incompletely committed entry from the ulog at kadmind
startup time.  For that matter, even if the db2 DB was power-fail
safe there'd be no point replaying an uncommitted entry from the
ulog as the libkadm5srv app (nor any client of it, as in the case of
kadmind) will not have received any notice of success -- it'd be
wrong to complete that operation later when the user thought it'd
failed.

[ghudson@mit.edu: merge with master, adjust comment]

ticket: 7552 (new)