BugLink: http://bugs.launchpad.net/bugs/1584912

[ Upstream commit a36a0d40 ]

In particular, make sure we check for decnet private presence
for loopback devices.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>