Comment 2 for bug 1682754

Reviewed: https://review.openstack.org/457159
Committed: https://git.openstack.org/cgit/openstack/sahara-image-elements/commit/?id=105577b6ca7edde849a288b4b09994507ae587ae
Submitter: Jenkins
Branch: master

commit 105577b6ca7edde849a288b4b09994507ae587ae
Author: Shu Yingya <email address hidden>
Date: Mon Apr 17 06:49:04 2017 +0000

    Fix 'navigator-keytrustee' repo not found error

    Build an image with DIB_CDH_MINOR_VERSION may fail
    because `navigator-keytrustee` doesn't release
    minor version sometimes, and then the repo will not
    be found.
    This patch determines whether the repo exists before
    writing repo url.

    Change-Id: I6bcd66264019847a08c2ba4c15da401567e57574
    Closes-Bug: 1682754