If sysvinit isn't in the DISTRO_FEATURES at all then the class should neuter itself, and not add build dependencies if possible.
Sent patch to the mailing list: http://lists.openembedded.org/pipermail/openembedded-core/2016-June/122700.html
This has been solved in commit: http://git.openembedded.org/openembedded-core/commit/?id=5b2139a79cd8c280e755923016b3a6e84413184e