Ticket 47891 - Admin Server reconfig breaks SSL config
1) Use mkdtemp to reduce the risk to disclose the sec file backup
location that is in the same file system as the original files
2) reconfig_backup_secfiles and reconfig_restore_secfiles expect
the admin config dir, e.g., "/etc/dirsrv/admin-serv" or the dir
specified by the environment variable.
3) Update (--update) did not call reconfig_restore_secfiles in which
restores and delete the backup dir.
4) If creating or accessing the sec backup dir fails, it issues a
fatal error and quits the reconfiguration.
Reviewed by email@example.com (Thank you, Rich!!)