staging: xgifb: delete LCDLenList

LCDLenList is redundant. It's only used for modifying a write-only stack
variable. Delete also related #defines.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>