Ticket 48284 - free entry when internal add fails
Bug Description: The entry passed to an internal add operaton is expected
to be consumed, but it is not freed during an internal
add when setting slapi_add_internal_pb() returns an error.
Fix Description: Free the entry in slapi_add_internal_pb() when the operation
is not allowed.
Reviewed by: nhosoi(Thanks!)
(cherry picked from commit 622be8bfbc942fe100b8880df72db26e99e1c954)