serial console, ports are not released

[Sahid Orentino]

When booting an instance with serial console activated, port(s) are allocated but never released since the code responsible to freeing port(s) is called after the domain is undefined from libvirt.
Also since the domain is already undefined, when calling the method '_lookup_by_name' an exception "DomainnotFound" is raised which makes not possible to correctly finish the deleting process

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/119781

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/119781
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=91227fe2d49cb42985cd3eb45fdc29e13bd019df
Submitter: Jenkins
Branch: master

commit 91227fe2d49cb42985cd3eb45fdc29e13bd019df
Author: Sahid Orentino Ferdjaoui <email address hidden>
Date: Mon Sep 8 14:42:50 2014 +0000

    libvirt: fix bug when releasing port(s)

    During the process of deleting an instance, if
    serial_console is enabled it has to check domain for
    allocated port(s) to be released - Currently this is doing
    after the domain has been undefined from libvirt which creates
    a bug. This patch fixes the problem by moving this part of code before
    undefining the domain.

    Also 5fa74bc0b2 moves that part of code inside the method
    _detach_encrypted_volumes which has nothing to do here.

    Change-Id: Ie187748deff7b0143d1ca26e767c6665746094c5
    Closes-Bug: #1366832