element rhel-common requires update for SSL cert path for REG_MODE=satellite

[Anshul Jain]

"diskimage-builder/diskimage_builder/elements/rhel-common/pre-install.d/00-rhel-registration"

rpm -Uvh "$REG_SAT_URL/pub/katello-ca-consumer-latest.noarch.rpm" || true

rpm - katello-ca-consumer-latest.noarch.rpm varies from one satellite server to another.
It will be better to have this rpm as user-defined parameter.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/547255

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/547255
Committed: https://git.openstack.org/cgit/openstack/diskimage-builder/commit/?id=b37a1e27cb746b164574355013f4139e4b154119
Submitter: Zuul
Branch: master

commit b37a1e27cb746b164574355013f4139e4b154119
Author: Anshul Jain <email address hidden>
Date: Thu Feb 22 21:54:52 2018 -0600

    Fix for passing user defined value for satellite cert for rhel-common.

    For 'satellite' mode of registration, rpm for rhel SSL certificate is
    hard coded to 'katello-ca-consumer-latest.noarch.rpm'. This commit adds
    functionality that provides an option to set this as defined in their
    satellite server.

    Change-Id: Ib176cfa209f5ac8a4b5da71419327b4237330904
    Closes-Bug: 1749947