DVB: dvb-usb-remote - fix oops when changing keymap

DVB USB remotes do not support changing keycode maps but set
input_dev->keycodesize and input_dev->keycodemax without setting
input_dev->keycode. This causes kernel oops when user tries to
look up (or change) current keymap.

While the proper fix would be to make remotes handle keymap changes
we'll just remove keycodemax and keycodesize initialization so
EVIOCGKEYCODE and EVIOCSKEYCODE will simply return -EINVAL.

http://bugzilla.kernel.org/show_bug.cgi?id=8312

Signed-off-by:  <olaf.kirch@oracle.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>