Add information text to Flashcart Info (#109)

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## Description
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Warns users that the display is meant to be empty.

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It is not yet implemented.

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src/menu/views/flashcart_info.c

@@ -19,8 +19,17 @@ static void draw (menu_t *menu, surface_t *d) {
     component_main_text_draw(
         ALIGN_CENTER, VALIGN_TOP,
         "FLASHCART INFORMATION\n"
+        "\n"
+        "\n"
+        "This feature is not yet supported.\n\n"
     );
 
+    // FIXME: Display:
+    // * cart_type
+    // * Firmware version
+    // * supported features (flashcart_features_t)
+
+
     component_main_text_draw(
         ALIGN_LEFT, VALIGN_TOP,
         "\n"