Before we had a bindings index in the documentation, the generated
header file was (somewhat unfortunately) often our best reference for
what a particular binding or property within a binding ends up doing,
so it made good sense to put the description in the generated file.
Now that we have HTML documentation that's a bit more digestible than
the generated file, though, we can just point users at that. Do that
and remove the inline description from the generated file.
This makes it possible to put C-style multiline comments in the
descriptions themselves, which will be done in subsequent patches.
Signed-off-by: Martí Bolívar <marti.bolivar@nordicsemi.no>