9p: patches for 4.1 merge window

Some accumulated cleanup patches for kerneldoc and unused variables
as well as some lock bug fixes and adding privateport option for RDMA.

A quick check shows some merge-conflicts versus current-tip on
   9p: use unsigned integers for nwqid/count
If you would prefer I can rebase, remerge and fix the patch but didn't
want to do that and look the for-next references.

Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
This tag has no release notes.