Fix pci-irq-affinity-agent xml parsing

[Lucas]

Brief Description
-----------------

The pci-irq-affinity-agent breaks when at least one interface driver name of an OpenStack instance `vfio`, the agent looks the interface inside a XML file. This is an agent requirement, but it shouldn't break the module. Other XML parsing also fails.

Severity
--------
Critical

Steps to Reproduce
------------------
Create an OpenStack instance (cpu_policy=dedicated) without a interface that uses `vfio` as driver. Check into `platform.log` for the error: Failed to access libvirt!

Expected Behavior
------------------
The agent checks all drivers and doesn't break if the required driver name doesn't exist.

Actual Behavior
----------------
In the first driver name that not starts with `vfio` the agent stops with the error: WARNING Failed to access libvirt! error='NoneType' object has no attribute 'get'

Reproducibility
---------------
Reproducible

System Configuration
--------------------
all

Branch/Pull Time/Commit
-----------------------
master

Test Activity
-------------
Feature Testing

Workaround
----------
N/A

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/starlingx/utilities/+/811131

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/starlingx/utilities/+/811986

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/starlingx/utilities/+/811986
Committed: https://opendev.org/starlingx/utilities/commit/2a0144af671226cacc6be277344db9b8ca46b854
Submitter: "Zuul (22348)"
Branch: master

commit 2a0144af671226cacc6be277344db9b8ca46b854
Author: Lucas Cavalcante <email address hidden>
Date: Thu Sep 30 11:50:54 2021 -0300

    Fix pci-irq-affinity-agent xml parser (devices)

    There is an issue in the agent's parser when it tries to parse domxml from instances
    that have multiple 'device/interface'. It tries to get the driver.name from
    all interfaces, including the ones without driver.name, e.g.:

    <interface type='vhostuser'>
      <mac address='aa:bb:cc:00:11:22'/>
      <source type='unix' path='/var/run/vswitch/0000000' mode='client'/>
      <model type='virtio'/>
      <alias name='net0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>

    This breaks the code:

    WARNING Failed to access libvirt! error='NoneType' object has no attribute 'get'

    Furthermore, for some network cards and/or older versions of libvirt, the software
    creates devices at 'device/hostdev'.

    This patch implements a way to find the device's driver and checks for its name.

    Test Plan:

    PASS: In a AIO-SX using The Intel® Ethernet Controller 10 Gigabit 82599EB,
    which supports 32 VFs per port with only SR-IOV configured with only SR-IOV
    configured.

    PASS: In a Standard using The Intel® Ethernet Controller 10 Gigabit 82599EB,
    which supports 32 VFs per port with only SR-IOV configured with SR-IOV and
    PCI Passthrough configured.

    Signed-off-by: hbrito <email address hidden>
    Signed-off-by: Lucas Cavalcante <email address hidden>
    Partial-bug: 1945201
    Change-Id: Ia486ab61286c2474878856ae5e7bce0216e618d0

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/starlingx/utilities/+/811131
Committed: https://opendev.org/starlingx/utilities/commit/8838bed45accab5b80838ee7f631a28c7c608e12
Submitter: "Zuul (22348)"
Branch: master

commit 8838bed45accab5b80838ee7f631a28c7c608e12
Author: Lucas Cavalcante <email address hidden>
Date: Mon Sep 27 10:35:29 2021 -0300

    Increase log messages for pci-irq-affinity-agent

    The pci-irq-affinity-agent does not give the user/admin useful information
    about the steps that the agent is running. It is necessary to add INFO
    and DEBUG logs to identify possible failures.

    Signed-off-by: Lucas Cavalcante <email address hidden>
    Closes-bug: 1945201
    Depends-on: Ia486ab61286c2474878856ae5e7bce0216e618d0
    Change-Id: If09c6ede3dd2d7fc49f14940d8ff902085ee3902