staging/lustre: Remove last_rcvd-file related data

last_rcvd (last received) is a special server-side file on the
Lustre FS that stores information about server filesystem and
also list of connected clients and their state. There's no
point in having any of tha ton the client, though.
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>