Fix list of possible architectures in Optional configuration parameters sections
Fix list of possible architectures in Optional configuration parameters sections

arm64 is only supported on AWS and Bare Metal; all other platforms
(besides IBM Power and IBM Z) are still limited to amd64.

vikram-redhat/openshift-docs,vikram-redhat/openshift-docs,vikram-redhat/openshift-docs,vikram-redhat/openshift-docs,vikram-redhat/openshift-docs