systemd: add keymap support

Signed-off-by: Stephan Raue <stephan@openelec.tv>
xkbcomp: update configure settings

Signed-off-by: Stephan Raue <stephan@openelec.tv>
xkeyboard-config: update configure settings

Signed-off-by: Stephan Raue <stephan@openelec.tv>