parser: remove XkbConfig rule This rule allows you to write file maps as: xkb_keycodes <BLA> = 5; [...] instead of the usual format which is: xkb_keycodes { <BLA> = 5; [...] }; This is not documented, It is also not used in xkeyboard-config, and I have never run into it otherwise. It also only allows one map per file. It *might* be used in some obscure place, but probably nothing we should care about; the simplified grammar is more useful for us now. Signed-off-by: Ran Benita <ran234@gmail.com>