tools: ynl: include dpll and mptcp_pm in C codegen

The DPLL and mptcp_pm families are pretty clean, and YNL C codegen
supports them fully with no changes. Add them to user space codegen
so that C samples can be written, and we know immediately if changes
to these families require YNL codegen work.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20240202004926.447803-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>