redhat: Switch to kernel-install for installing UKIs
JIRA: https://issues.redhat.com/browse/RHEL-19486
systemd >= 252-20 brings kernel-install support for UKIs, drop the temporary RHEL only solution.
Signed-off-by: Vitaly Kuznetsov vkuznets@redhat.com
Edited by Vitaly Kuznetsov