python: Update wrapping tool to support multiple hierarchy files

To keep the argument parsing code simple, each hierarchy file has to be
specified using a dedicated --types.

Change-Id: Ib2725a1fb312c7ff1a26556b881653a8ab783172
python: Do not create a new hints file if a kit bundles only one module

Change-Id: Iaef3f414ca5fdaea8a6b7fa26538d7a32638a4f7