EVIOCSKEYCODE macros to be <= KEY_MAX. Check off-by one mistakes
       in keycodemax usage. There was a lot of potential for overwriting
       memory. Also enlarge NR_KEYS to 256 while we're at it.
Found-by: Georgi Guninski <guninski@guninski.com>
Initial-patch-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Vojtech Pavlik <vojtech@suse.cz>