run dbginfo debugging script as part of must-gather and install gather

In the OCP docs for installing OCP on IBM Z, in the "Collecting debugging information" section, it asks the user to oc debug into the node to execute the dbginfo script: https://access.redhat.com/documentation/en-us/openshift_container_platform/4.8/html/installing/installing-with-rhel-kvm-on-ibm-z-and-linuxone. This script : https://github.com/ibm-s390-linux/s390-tools/blob/master/scripts/dbginfo.sh is part of the s390-utils rpm package included as part of RHCOS and collects system related information on a Z system.

But the user should not be required to go into the node and run a script. the collection of this information should be made a part of the must-gather and the installer gather (for debugging bootstrap failures through installer).