Flag LAYOUT macros still defined in .h files (#23260)

lib/python/qmk/info.py

@@ -78,7 +78,7 @@ def _find_invalid_encoder_index(info_data):
     return ret
 
 
-def _validate_layouts(keyboard, info_data):
+def _validate_layouts(keyboard, info_data):  # noqa C901
     """Non schema checks
     """
     col_num = info_data.get('matrix_size', {}).get('cols', 0)
@@ -92,6 +92,11 @@ def _validate_layouts(keyboard, info_data):
     if len(layouts) == 0 or all(not layout.get('json_layout', False) for layout in layouts.values()):
         _log_error(info_data, 'No LAYOUTs defined! Need at least one layout defined in info.json.')
 
+    # Make sure all layouts are DD
+    for layout_name, layout_data in layouts.items():
+        if layout_data.get('c_macro', False):
+            _log_error(info_data, f'{layout_name}: Layout macro should not be defined within ".h" files.')
+
     # Make sure all matrix values are in bounds
     for layout_name, layout_data in layouts.items():
         for index, key_data in enumerate(layout_data['layout']):