Kukui devices krane, kodana, and kakadu use detachable keyboards, which
only have switches to be registered.

Change the keyboard node's compatible of those boards to the newly
introduced "google,cros-ec-keyb-switches", which won't include matrix
properties.
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Link: https://lore.kernel.org/r/20220527045353.2483042-1-hsinyi@chromium.orgSigned-off-by: Matthias Brugger <matthias.bgg@gmail.com>