Added derivation of TDF base class, for AVR8 targets.

Includes initialisation and validation code.

build/scripts/TargetDescriptionFiles/ModuleInstance.php

@@ -0,0 +1,12 @@
+<?php
+namespace Bloom\BuildScripts\TargetDescriptionFiles;
+
+require_once __DIR__ . "/RegisterGroup.php";
+
+class ModuleInstance
+{
+    public ?string $name = null;
+
+    /** @var RegisterGroup[] */
+    public array $registerGroupsMappedByName = [];
+}