Issue #2167975 by amateescu, swentel: Entity_reference_create_instance does...

Issue #2167975 by amateescu, swentel: Entity_reference_create_instance does not support cardinality.

core/modules/entity_reference/entity_reference.module

@@ -191,10 +191,12 @@ function entity_reference_query_entity_reference_alter(AlterableInterface $query
  * @param array $selection_handler_settings
  *   An array of settings supported by the selection handler specified above.
  *   (e.g. 'target_bundles', 'sort', 'auto_create', etc).
+ * @param int $cardinality
+ *   The cardinality of the field.
  *
  * @see \Drupal\entity_reference\Plugin\entity_reference\selection\SelectionBase::settingsForm()
  */
-function entity_reference_create_instance($entity_type, $bundle, $field_name, $field_label, $target_entity_type, $selection_handler = 'default', $selection_handler_settings = array()) {
+function entity_reference_create_instance($entity_type, $bundle, $field_name, $field_label, $target_entity_type, $selection_handler = 'default', $selection_handler_settings = array(), $cardinality = 1) {
   // If a field type we know should exist isn't found, clear the field cache.
   if (!\Drupal::service('plugin.manager.field.field_type')->getDefinition('entity_reference')) {
     field_cache_clear();
@@ -209,6 +211,7 @@ function entity_reference_create_instance($entity_type, $bundle, $field_name, $f
       'name' => $field_name,
       'type' => 'entity_reference',
       'entity_type' => $entity_type,
+      'cardinality' => $cardinality,
       'settings' => array(
         'target_type' => $target_entity_type,
       ),