Fix the $location parameter type in the unregister_nav_menu() DocBlock.

`$location` is a string, not an array.

Props ipm-frommen.
Fixes #30098.


git-svn-id: https://develop.svn.wordpress.org/trunk@30019 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/nav-menu.php

@@ -81,8 +81,7 @@ function register_nav_menus( $locations = array() ) {
 /**
  * Unregisters a navigation menu for a theme.
  *
- * @param array $location the menu location identifier
- *
+ * @param string $location The menu location identifier.
  * @return bool True on success, false on failure.
  */
 function unregister_nav_menu( $location ) {