profiles.desc: Explicitly indicate maintainers for every profile

profiles.desc: Explicitly indicate maintainers for every profile

Add @MAINTAINER comments before every profile set indicating
the effective maintainer for the following set of profiles. While most
of those entries may seem obvious at first, I expect that some
of the sub-profiles will eventually 'change hands', e.g. the /hardened
sub-profiles would be maintained by Hardened, etc.

The main goal is to provide a clear indication of who maintains every
profile. This will be of great help both to bug-wranglers (who currently
have to pretty much guess who to assign profile bugs to) and to other
developers who plan to commit larger changes and want to get ACK from
appropriate parties.