legacy_net_info guard incompatible with new-style NetworkInfo

[Rick Harris]

In order to fix https://bugs.launchpad.net/nova/+bug/1152426

a guard was added to _init_instance in compute manger.

The problem is that the guard assumed that `legacy_net_info` would always be a tuple which is not true. Depending on the config, it may be a list of tuples, or a NetworkInfo object.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/26042

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/26042
Committed: http://github.com/openstack/nova/commit/948d1fefe6cb1e17c5567d3cf3313e13c16a3d57
Submitter: Jenkins
Branch: master

commit 948d1fefe6cb1e17c5567d3cf3313e13c16a3d57
Author: Rick Harris <email address hidden>
Date: Wed Apr 3 21:09:50 2013 +0000

    Fix legacy_net_info guard

    The existing code assumes that `legacy_net_info` is always in legacy
    mode, meaning a list of tuples which causes it to break when passed a
    new-style NetworkInfo object.

    Fixes bug 1164152

    Change-Id: I2131d9b24045cd7531454b65d97776b11ec3ab02

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/grizzly
Review: https://review.openstack.org/26613

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/26613
Committed: http://github.com/openstack/nova/commit/b2ec66823baf2a5094a9b398c2554bdcd2aba928
Submitter: Jenkins
Branch: stable/grizzly

commit b2ec66823baf2a5094a9b398c2554bdcd2aba928
Author: Rick Harris <email address hidden>
Date: Wed Apr 3 21:09:50 2013 +0000

    Fix legacy_net_info guard

    The existing code assumes that `legacy_net_info` is always in legacy
    mode, meaning a list of tuples which causes it to break when passed a
    new-style NetworkInfo object.

    Fixes bug 1164152

    Change-Id: I2131d9b24045cd7531454b65d97776b11ec3ab02
    (cherry picked from commit 948d1fefe6cb1e17c5567d3cf3313e13c16a3d57)