This program opens and "listens" on the new nfsd/cld rpc_pipefs pipe.
The code here doesn't actually do anything on stable storage yet. That
will be added in a later patch.
The patch also adds a autoconf enable switch for the new daemon that
defaults to "no", and a test for the upcall description header file.
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve Dickson <steved@redhat.com>