debian/*.service: allow keyboard to bypass "Other vibrations"
HFD service is now implementing "Other vibrations" settings. This time, it won't have the hard-coded list of clients to bypass. Instead, there's a privileged DBus path which is protected by AppArmor and can be used in the client plugin with an environment variable.
Without hfd-service!13 (merged), this does nothing. This allows this MR to be merged before the hfd-service MR, which ensures that the image will never be in a "broken" state.