lk201: remove obsolete driver

Remove the old-fashioned lk201 driver under drivers/tc/ that used to be
used by the old dz.c and zs.c drivers, which is now orphan code referred to
from nowhere and does not build anymore.  A modern replacement is available
as drivers/input/keyboard/lkkbd.c.

There are no plans to do anything about this piece of code and it does not
fit anywhere anymore, so it is not just a matter of maintenance or the lack
of.  There are still some bits that might be added to the new lkkbd.c
driver based on the old code, and the embedded hardware documentation which
is otherwise quite hard to get hold of might be useful to keep too.  Both
of these can be done separately though.  RIP.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>