9556 logadm timestamps should not leak into the configfile

Review Request #1091 — Created May 28, 2018 and submitted — Latest diff uploaded


Issue: https://www.illumos.org/issues/9556

When using wildcard patterns in the configfile logadm will record the
timestamps of all matched and rotated files in the timestamp file.
If the config file is then edited using logadm -w or logadm -r
these timestamps can not be matched to existing rules in the configfile
and will end up beeing written back into it.

This is confusing, especially when the patterns match many files and the
configfile becomes huge.

In addition to the fix for this there is some cleanup in lut.c and a
small change to testcase "logadm21" which allows the tests to run as
non-root users.

Tested manually and with the newly added tests like this:

/opt/onbld/bin/bldenv -d illumos.sh -c "cd usr/src/cmd/logadm && dmake -m serial test"