[dovecot/core] a8adad: auth: Fix %{ldap_dn} not to leak memory

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/dovecot/core
  Commit: a8adad33c80f82beb3c3529065a3d2b936cfd2fc
      https://github.com/dovecot/core/commit/a8adad33c80f82beb3c3529065a3d2b936cfd2fc
  Author: Timo Sirainen <timo.sirainen at dovecot.fi>
  Date:   2017-10-19 (Thu, 19 Oct 2017)

  Changed paths:
    M src/auth/db-ldap.c

  Log Message:
  -----------
  auth: Fix %{ldap_dn} not to leak memory