Fix controller base code: Update function is not using model_args

The model_args variable is used to pass information to functions.
Specially in functions of sub-collections and sub-resources, it is used
to pass the main collections and resources names/classes. The wrapper
update function from control base was not using model_args, then some
resouces might miss this information.

Signed-off-by: Rodrigo Trujillo <rodrigo.trujillo@linux.vnet.ibm.com>