Comment 5 for bug 1886062

Reviewed: https://review.opendev.org/743712
Committed: https://git.openstack.org/cgit/starlingx/root/commit/?id=95611f4adfdd73d846e9cdc040afe4ce1a7bb66a
Submitter: Zuul
Branch: r/stx.4.0

commit 95611f4adfdd73d846e9cdc040afe4ce1a7bb66a
Author: zhipengl <email address hidden>
Date: Wed Jul 15 01:47:53 2020 +0800

    Add --config-file argument for docker image build script

    build-stx-base.sh and build-stx-images.sh need to accept a
    new argument (--config-file <path>) specifying a path to a
    config file.
    These commands automatically look for the config files at
    the predetermined location, and apply them if found. If not
    found, continue without error. If optional argument
    --config-file is added, These commands will use specified
    configfile instead of predetermined one.

    Test pass on local build enviroment.

    Closes-Bug: 1886062

    Change-Id: I476e38064d1515d3d0a0d49c789f1d472d8ca1cc
    Signed-off-by: zhipengl <email address hidden>
    (cherry picked from commit 4d6af626b1976987e614487a9c7a9293e5427113)