Added @deprecated PHPDoc comments to constants

Author: jorgsowa

ext/date/php_date.stub.php

@@ -83,18 +83,21 @@
 /**
  * @var int
  * @cvalue SUNFUNCS_RET_TIMESTAMP
+ * @deprecated
  */
 const SUNFUNCS_RET_TIMESTAMP = UNKNOWN;
 
 /**
  * @var int
  * @cvalue SUNFUNCS_RET_STRING
+ * @deprecated
  */
 const SUNFUNCS_RET_STRING = UNKNOWN;
 
 /**
  * @var int
  * @cvalue SUNFUNCS_RET_DOUBLE
+ * @deprecated
  */
 const SUNFUNCS_RET_DOUBLE = UNKNOWN;