Fix broken trust warnings

Warning should be shown only for parent entries of trust domain. Subdomains do not contain ipaNTSecurityIdentifier attribute at all.

https://fedorahosted.org/freeipa/ticket/5737

Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>

ipalib/plugins/trust.py

@@ -597,7 +597,9 @@ class trust(LDAPObject):
 
         try:
             entries, truncated = ldap.find_entries(
-                base_dn=DN(self.container_dn, self.api.env.basedn),
+                base_dn=DN(self.api.env.container_adtrusts,
+                           self.api.env.basedn),
+                scope=ldap.SCOPE_ONELEVEL,
                 attrs_list=['cn'],
                 filter='(&(ipaNTTrustPartner=*)'
                        '(!(ipaNTSecurityIdentifier=*)))',