Removing https://github.com/openshift/machine-config-operator/issues/1720 from the tracker since it's only tangentially related to this problem. https://github.com/openshift/installer/pull/3589 resolves this for masters, and https://bugzilla.redhat.com/show_bug.cgi?id=1834883 is a clone of this bz which tracks a similar revert for cluster-api-provider-baremetal (which will be required to fix this interface regression for workers). We're discussing option of how we can rework things such that we can satisfy the requirement that led to https://github.com/openshift/installer/pull/3589 (ability to put the external nic on a tagged network) without breaking any existing interfaces.
I checked this bug in 4.5.0-0.nightly-2020-06-04-025914 version,ifcfg-<ifname> files are present on the RHCOS filesystem and so the interfaces disabled, problem fixed. (I added attachment that prove it)
Created attachment 1695020 [details] ifcfg-<ifname> files are present
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHBA-2020:2409