staging/lustre: Update internal client version.

While initial code drop was corresponding to 2.3.64, lots of
different changes went in since then, and also quite a bunch of fixes,
but almost none of the new features.
Code-wise we are almost at 2.5.0, so let's call it 2.4.60 - this is a
version that was never reached in the actual pre-2.5 development, so
it should be a clear distinction of where we are now.

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>