xkb: fix GetKbdByName()
This request is a bit tricky: it has some variable length parameters (made of an CARD8 length field and payload bytes). Using separate list parameters won't work here, as this would pad them to 4-byte boundaries, which is not the case here.
Compromising by just adding one byte list and let the caller take care of assembling the correct payload.
Signed-off-by: Enrico Weigelt, metux IT consult info@metux.net