Comment 2 for bug 1978320

Reviewed: https://review.opendev.org/c/starlingx/config/+/845383
Committed: https://opendev.org/starlingx/config/commit/cf0161285e6cc55052e4d4865e6e41eb04e260ac
Submitter: "Zuul (22348)"
Branch: master

commit cf0161285e6cc55052e4d4865e6e41eb04e260ac
Author: Andy Ning <email address hidden>
Date: Fri Jun 10 10:22:57 2022 -0400

    Debian: fix system registry image commands

    On Debian system regirstry image commands such as
    system registry-image-list fails with traceback in sysinv log.

    The root cause is that the command is looking for system trusted
    CA bundle in a hardcoded path "/etc/ssl/certs/ca-bundle.crt".
    But on Debian the CA bundle is /etc/ssl/certs/ca-certificates.crt

    Fixed this by adding a generic function to find the CA bundle in
    a list that have the CA bundle path for Debian, CentOS, Suse and
    FreeBSD/OpenBSD.

    Test Plan for Debian and CentOS:
    PASS: package build, image build
    PASS: system bootstrap, controller unlock
    PASS: system registry-image-list succeed without error

    Closes-Bug: 1978320
    Signed-off-by: Andy Ning <email address hidden>
    Change-Id: I9fbf19ea6a78c1e4d93855815f239eb29b6f7551