Keyboard daemon was calling into the wrong module name. There are only
so much kcminit modules, and all of them are required to be named and
referenced with a "kcm_" prefix.

Postmortem:

- Mouse settings' saving and loading worked fine.
- Changing settings on the fly worked fine, and if they were not loaded
  before due to this bug, KCM loaded them and applied, after which
  mouse worked fine until disconnected.
- Starting computer with mouse already connected worked fine.
- Plug&Play (i.e. connecting mouse after session has started) was the
  only thing that was broken, because this reconfiguration failed to
  launch the proper mouse module.

Co-Authored-By: David Edmundson <kde@davidedmundson.co.uk>
BUG: 435113
FIXED-IN: 5.24.7, 5.25.4, 5.26