connman: update to connman-1.23

Signed-off-by: Stephan Raue <stephan@openelec.tv>
connman: Require dbus.socket instead of syslog.target in systemd unit files, see also http://git.kernel.org/cgit/network/connman/connman.git/commit/?id=cfa24d924a0fe046d65120f21b480313b45e196b

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