dirmngr: Fix build with --disable-ldap.
* dirmngr/dirmngr.c (parse_rereadable_options) [USE_LDAP]: Conditionalize.
(cherry picked from commit c8b2162c0e7eb42b74811b7ed225fa0f56be4083)
- Reported-by: Phil Pennock
- Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>