Ticket 49016 - (un)register/migration/remove may fail if there is no suffix on 'userRoot' backend
Bug Description:
Previous fix was incomplete in case none of the backend entries have
'nsslapd-suffix' value
Fix Description:
Just return if $suffix keep unmodified
https://fedorahosted.org/389/ticket/49016
Reviewed by: nhosoi
Platforms tested: F23, F25
Flag Day: no
Doc impact: no
(cherry picked from commit bd5fdfc8f4a560eae99672b712235c1260ee42b0)