openldap: hide configurables when libopenldap is not enabled

openldap: hide configurables when libopenldap is not enabled

When openldap is not enabled, the following configurables remain present
in the config:

CONFIG_OPENLDAP_DEBUG=y
\# CONFIG_OPENLDAP_CRYPT is not set
\# CONFIG_OPENLDAP_MONITOR is not set
\# CONFIG_OPENLDAP_DB47 is not set
\# CONFIG_OPENLDAP_ICU is not set

This patch adds a libopenldap dependency for these options, removing the
above from .config when libopenldap is not used. Further, move these
configurables to Config.in.

Signed-off-by: Matthew Hagan <mnhagan88@gmail.com>