Fix salesagility#10541 - Relation M2M between Security Groups and Sec…

…urity Groups raises an error

data/Relationships/M2MRelationship.php

@@ -145,15 +145,15 @@ public function add($lhs, $rhs, $additionalFields = array())
         //Need to hijack this as security groups will not contain a link on the module side
         //due to the way the module works. Plus it would remove the relative ease of adding custom module support
 
-        if (get_class($rhs) != 'User' && get_class($rhs) != 'ACLRole' && get_class($lhs) == 'SecurityGroup') {
+        if (get_class($rhs) != 'User' && get_class($rhs) != 'ACLRole' && get_class($lhs) == 'SecurityGroup' && get_class($rhs) != 'SecurityGroup') {
             $rhs->$rhsLinkName->addBean($lhs);
             $this->callBeforeAdd($rhs, $lhs, $rhsLinkName);
 
             $dataToInsert = $this->getRowToInsert($lhs, $rhs, $additionalFields);
             $this->addRow($dataToInsert);
             $rhs->$rhsLinkName->addBean($lhs);
             $this->callAfterAdd($lhs, $rhs, $lhsLinkName);
-        } elseif (get_class($lhs) != 'User' && get_class($lhs) != 'ACLRole' && get_class($rhs) == 'SecurityGroup') {
+        } elseif (get_class($lhs) != 'User' && get_class($lhs) != 'ACLRole' && get_class($rhs) == 'SecurityGroup' && get_class($lhs) != 'SecurityGroup') {            
             $lhs->$lhsLinkName->addBean($rhs);
             $this->callBeforeAdd($lhs, $rhs, $lhsLinkName);