Make Jakarta Data available in WFP.

This may require a subsystem, or perhaps just modules and a layer. The example Jakarta Data TCK run only requires modules, so we should explore what the requirements are around a subsystem.

Even if a subsystem isn't required to do a basic integration, adding a trivial one may be the right thing, as it allows future expansion including JD-specific content in the deployment=/subsystem= tree without requiring a breaking change where users have to add a new subsystem.