scripts: dts: gen_driver_kconfig_dts: Skip empty yaml files

The YAML parsing will currently return a None-type if no input data
is empty, and the subsequent check for a substring will cause an
exception.

Signed-off-by: Allan Norgaard <[email protected]>

Author: allannk

scripts/dts/gen_driver_kconfig_dts.py

@@ -80,7 +80,7 @@ def main():
                 print(f"WARNING: '{binding_path}' appears in binding "
                       f"directories but isn't valid YAML: {e}")
                 continue
-        if 'compatible' not in raw:
+        if raw is None or 'compatible' not in raw:
             continue
 
         compat_list.append(raw['compatible'])