lxc-user-nic: dont risk passing EOF

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
lxc-user-nic: use common code from network.c

This pulls a lot of common code out of lxc_user_nic.c.  It also
moves one function from conf.c that was duplicated in lxc_user_nic.c
(It removes a DEBUG statement because (a) it doesn't seem actually
useful and (b) DEBUG doesn't work in network.c).

Also replace the old test of only parsing code with a skeleton for
a full test.  (Note - the test will need some work, it's just there
as do-what-i-mean code example)

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
Fix stupid architecture error.

From 38cfabdbe0e46f5a0ed20687fcda48424b4a7b6d Mon Sep 17 00:00:00 2001
From: "Michael H. Warfield" <mhw@WittsEnd.com>
Date: Mon, 25 Nov 2013 10:34:48 -0500
Subject: [PATCH 1/2] Fix stupid architecture error.
Organization: Thaumaturgy & Speculums Technology

Fix stupid architecture error.

Stupid error and I did it!  Fixed hard coded x86_64 in several spots.

Signed-off-by: Michael H. Warfield <mhw@WittsEnd.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>