ynl-gen-c.py: allow directional model for kernel mode

Directional model limitation is only applicable for uapi mode.
For kernel mode, the code is generated correctly using right cmd values
for do/dump requests. Lift the limitation.
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20230803111340.1074067-4-jiri@resnulli.usSigned-off-by: Jakub Kicinski <kuba@kernel.org>

tools/net/ynl/ynl-gen-c.py

@@ -2317,7 +2317,7 @@ def main():
         return
 
     supported_models = ['unified']
-    if args.mode == 'user':
+    if args.mode in ['user', 'kernel']:
         supported_models += ['directional']
     if parsed.msg_id_model not in supported_models:
         print(f'Message enum-model {parsed.msg_id_model} not supported for {args.mode} generation')