If I run testpmd as primary and dumpcap as secondary process with a vdev (null,
tap, etc). The the vdev device is not setup in the secondary process.

Example:
# ./build/app/dpdk-dumpcap  -D
EAL: Detected CPU lcores: 8
EAL: Detected NUMA nodes: 1
EAL: Detected static linkage of DPDK
EAL: Multi-process socket /var/run/dpdk/rte/mp_socket_51860_420642a7f63
vdev_action(): failed to add vdev, net_null0




This works with 23.11 and earlier releases and is a regression.
Not only is this a regression bug, it shows a short coming in the CI system for
not catching it.

Bisection reveals the commit causing the regression is:

commit 6666628362c94a0b567a39a0177539c12c97d999
Author: Mingjin Ye <mingjinx.ye@intel.com>
Date:   Fri Sep 1 07:24:09 2023 +0000

    bus/vdev: fix devargs in secondary process

    When a device is created by a secondary process, an empty devargs is
    temporarily generated and bound to it. This causes the device to not
    be associated with the correct devargs, and the empty devargs are not
    released when the resource is freed.

    This patch fixes the issue by matching the devargs when inserting a
    device in secondary process.

    Fixes: dda987315ca2 ("vdev: make virtual bus use its device struct")
    Fixes: a16040453968 ("eal: extract vdev infra")
    Cc: stable@dpdk.org

    Signed-off-by: Mingjin Ye <mingjinx.ye@intel.com>
    Acked-by: Anatoly Burakov <anatoly.burakov@intel.com>