Feature: #70033 - Introduced TCA option showIconTable for selectSingle fields

See forge#70033

Description

A new option showIconTable has been introduced for select fields with render type selectSingle to enforce or prevent the icon table underneath the field. By default the icon table is not shown.

Example

// Enforce icon table showing flags
$GLOBALS['TCA']['tt_content']['columns']['sys_language_uid']['config']['showIconTable'] = true;