Conditional enable the ldap configuration

If any of the existing ldap config(openldap/AD) is
already enabled,The other ldap configuration can't be
enabled.

TestedBy: Unit-Tested

          Tested the above behaviour.It throws the
          error back if try to enable the configuration
          when there is already active configuration.

          If there is no active configuration then it
          allows to enable the configuration.

Signed-off-by: Ratan Gupta <ratagupt@linux.vnet.ibm.com>
Change-Id: I5b6008036152cd36e5422bb372a05c8a3ec3d24b
diff --git a/phosphor-ldap-config/ldap_config.hpp b/phosphor-ldap-config/ldap_config.hpp
index 6eceb50..0d2adf1 100644
--- a/phosphor-ldap-config/ldap_config.hpp
+++ b/phosphor-ldap-config/ldap_config.hpp
@@ -183,6 +183,12 @@
      */
     bool deserialize();
 
+    /** @brief enable or disable the service with the given value
+     *  @param[in] value - enable/disble
+     *  @returns value of changed status
+     */
+    bool enableService(bool value);
+
   private:
     bool secureLDAP;
     std::string lDAPBindPassword{};