check-dbus-services: do not special-case com.chaiwala.Updater

This came from the chaiwala-btrfs package, which we haven't shipped
since 15.12.

Reviewed-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Signed-off-by: Simon McVittie <simon.mcvittie@collabora.co.uk>
Differential Revision: https://phabricator.apertis.org/D3897