I recently went looking for users of the add() method in struct
bus_type, only to discover that there are none.  A query to Pat
confirmed that it is surplus and should come out.  So here's a patch
that does it.

While I was at it, I updated Documentation/driver-model/bus.txt to at
least get rid of the blatantly untrue stuff; it is still rather far from
being up to date, however.  I may be able to fix that later on.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>