htmlform: Fix multiple PHPDoc annotations in htmlform module

- Add @param annotation for $params variable for __construct() method
  in the HTMLExpiryField class.
- Add @throws annotation for getOptionsOOUI() method that throws a
  MWException and remove "@return array" as this method only throw an
  exception now.

Change-Id: I292f6ae04b840f6f6f74b7c92f834f056659fbe2

includes/htmlform/fields/HTMLExpiryField.php

@@ -15,6 +15,7 @@ class HTMLExpiryField extends HTMLFormField {
 
 	/**
 	 * Relative Date Time Field.
+	 * @param array $params
 	 */
 	public function __construct( array $params = [] ) {
 		parent::__construct( $params );

includes/htmlform/fields/HTMLMultiSelectField.php

@@ -121,7 +121,7 @@ class HTMLMultiSelectField extends HTMLFormField implements HTMLNestedFilterable
 
 	/**
 	 * Get options and make them into arrays suitable for OOUI.
-	 * @return array Options for inclusion in a select or whatever.
+	 * @throws MWException
 	 */
 	public function getOptionsOOUI() {
 		// Sections make this difficult. See getInputOOUI().