input/chronovu_la8: claim responsibility for LA16 files, devel comments
The chronovu_la8 input module is capable of handling either file type,
generated by LA8 or LA16 vendor software. Automatic detection is not
available, but user provided channel counts work fine.
Adjust the input module's name and description, and claim support for
.kdt as well as .kd1 files.
Add developer notes on implementation details, the file content's
constraints, and potential future adjustment.