fix deprecations: getName -> getBlockPrefix in forms

Form/Type/ClosingMotiveType.php

@@ -1,4 +1,4 @@
-<?php
+public function getBlockPrefix<?php
 
 namespace Chill\PersonBundle\Form\Type;
 
@@ -25,7 +25,7 @@ class ClosingMotiveType extends AbstractType
         }
     }
 
-    public function getName()
+    public function getBlockPrefix()
     {
         return 'closing_motive';
     }