avahi: remove avahi-dnsconfd support

Signed-off-by: Stephan Raue <stephan@openelec.tv>
udisks: start udisks daemon manually so its there on xbmc start

Signed-off-by: Stephan Raue <stephan@openelec.tv>
polkit: convert to new package format

Signed-off-by: Stephan Raue <stephan@openelec.tv>
polkit: enable systemd support

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