linux-phytec-fsl

nfsd: document kernel interfaces for nfsd configuration

These are only needed by nfs-utils.  But I needed to remind myself how
they worked recently and thought this might be helpful.  It's short and
incomplete for now as I was only interested in startup, shutdown, and
configuration of listening sockets.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>