Bring back to life ng_pipe insertion on our links. For this to work

Bring back to life ng_pipe insertion on our links.  For this to work
you'll need to fetch the latest kernel sources from my home dir
at imunes.tel.fer.hr or from p4.  Note that the scheduler for ng_pipe
in -CURRENT at this point in time cannot provide resolution better than
kernel tick intervals, so you'll probably wish to configure your kernels
with high HZ setting - default in -CURRENT is 1000 HZ which should be
fine for proof-of-concept experiments.

Note that ng_pipe in -CURRENT is stripped off of XCP and [GA]RED
functions, but we never used those directly in IMUNES anyway so noone
should be hurt...

Bug found by:
Submitted by:
Reviewed by:
Approved by:
Obtained from: