staging: lustre: fold lu_object_new() into lu_object_find_at()

lu_object_new() duplicates a lot of code that is in
lu_object_find_at().
There is no real need for a separate function, it is simpler just
to skip the bits of lu_object_find_at() that we don't
want in the LOC_F_NEW case.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>