m68k: Atari input drivers cleanup

m68k: Atari input drivers cleanup:
  - memleak on failed init/register of input devices fixed
  - correct keycodes table (Atari keycodes are almost, but not entirely, equal
    to Linux keycodes).

Signed-off-by: Michael Schmitz <schmitz@biophys.uni-duesseldorf.de>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>