staging: lustre: lnet: discard CFS_ALLOC_PTR

These trivial wrappers hurt readability and
as they use kvmalloc, they are overly generic.

So discard them and use kmalloc/kfree as is
normal in Linux.

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