[3.3] More docblock fixes

Author: nicolas-grekas

Normalizer/DateTimeNormalizer.php

@@ -24,9 +24,6 @@ class DateTimeNormalizer implements NormalizerInterface, DenormalizerInterface
 {
     const FORMAT_KEY = 'datetime_format';
 
-    /**
-     * @var string
-     */
     private $format;
 
     /**
@@ -112,8 +109,6 @@ public function supportsDenormalization($data, $type, $format = null)
     /**
      * Formats datetime errors.
      *
-     * @param array $errors
-     *
      * @return string[]
      */
     private function formatDateTimeErrors(array $errors)