[dovecot/core] 2dc8e2: configure: Fixed (again) --with-ldap=plugin

[GitHub]

  Branch: refs/heads/master-2.2
  Home:   https://github.com/dovecot/core
  Commit: 2dc8e2db12512cb249264276c708a69507e12396
      https://github.com/dovecot/core/commit/2dc8e2db12512cb249264276c708a69507e12396
  Author: Timo Sirainen <timo.sirainen at dovecot.fi>
  Date:   2016-04-29 (Fri, 29 Apr 2016)

  Changed paths:
    M configure.ac

  Log Message:
  -----------
  configure: Fixed (again) --with-ldap=plugin