Comment 2 for bug 1915182

Reviewed: https://review.opendev.org/c/starlingx/root/+/786137
Committed: https://opendev.org/starlingx/root/commit/0ce0a1e5e3c5318a9a530c1d5ad90a7e19755a45
Submitter: "Zuul (22348)"
Branch: f/centos8

commit 0ce0a1e5e3c5318a9a530c1d5ad90a7e19755a45
Author: Scott Little <email address hidden>
Date: Tue Feb 9 13:12:06 2021 -0500

    build-img fails if not run under $MY_WORKSPACE

    Build-img may need to generate a patch that is to be applied to the
    image being produced. The patch build tool drops the patch into
    the current directory. No explicit working directory was set.
    A subsequent step tries to apply the patch, but assumes it is in
    $MY_WORKSPACE.

    We want all build artifacts to be placed under $MY_WORKSPACE, so
    set $MY_WORKSPACE as the current directory before creating the patch.

    Closes-Bug: 1915182
    Signed-off-by: Scott Little <email address hidden>
    (cherry picked from commit 71d5ae9df9268be2803e2a45277e65c7c84c1fdb)
    Change-Id: I8c34bc0c4697934cee2ca07334f817311c574872