mdbox: Remove refcount=0 records from map index on the first purge (not second).
mdbox: Remove refcount=0 records from map index on the first purge (not second).

LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot