Ticket 47614 - Possible to specify invalid SASL mechanism in nsslapd-allowed-sasl-mechanisms
Bug Description: Invalid values could be specified in the allowed sasl mechanisms configuration
attribute. These values are directly passed to the sasl library.
Fix Description: Follow RFR 4422, only allow upto 20 characters that are ASCII upper-case letters,
digits, hyphens, or underscores.
https://fedorahosted.org/389/ticket/47614
Reviewed by: richm(Thanks!)
(cherry picked from commit 7e8a5fc7183f7c08212bfb746ea8c5ceedee0132)