LDAP: start or stop nslcd on service starting

`nslcd` service should be started only if there is a valid endpoint.
This commit adds a call that starts or stops `nslcd.service` after
the Dbus objects has been deserialized, depending by the presence of
enabled endpoint.

Tested:
1. Made sure `nslcd` is stopped by default.
2. Added a configuration for AD/LDAP endpoint and made sure `nslcd`
   is started.
3. Rebooted BMC and made sure `nslcd` is started.

Change-Id: I06d91cb450e92bdfb12c4f65dce4e250113ab461
Signed-off-by: Alexander Filippov <a.filippov@yadro.com>
diff --git a/phosphor-ldap-config/ldap_config_mgr.cpp b/phosphor-ldap-config/ldap_config_mgr.cpp
index e8490e4..1218d18 100644
--- a/phosphor-ldap-config/ldap_config_mgr.cpp
+++ b/phosphor-ldap-config/ldap_config_mgr.cpp
@@ -12,6 +12,7 @@
 namespace ldap
 {
 
+constexpr auto nslcdService = "nslcd.service";
 constexpr auto nscdService = "nscd.service";
 constexpr auto LDAPscheme = "ldap";
 constexpr auto LDAPSscheme = "ldaps";
@@ -211,6 +212,9 @@
         openLDAPConfigPtr->restoreRoleMapping();
         openLDAPConfigPtr->emit_object_added();
     }
+
+    startOrStopService(phosphor::ldap::nslcdService,
+                       ADConfigPtr->enabled() || openLDAPConfigPtr->enabled());
 }
 
 } // namespace ldap