erpt: implement new 21.0.0 commands

libraries/libstratosphere/include/stratosphere/erpt/srv/erpt_srv_types.hpp

@@ -124,6 +124,10 @@ namespace ams::erpt::srv {
         }
     }
 
+    constexpr inline bool IsValidCategory(CategoryId id) {
+        return FindCategoryIndex(id).has_value();
+    }
+
     constexpr inline CategoryId ConvertFieldToCategory(FieldId id) {
         const auto index = FindFieldIndex(id);
         AMS_ASSERT(index.has_value());