As described in the Ironic spec - https://review.opendev.org/c/openstack/ironic-specs/+/774681, additional fields are being added to the Ironic bios API in to include fields retrieved from the Redfish BIOS registry. This is currently up for review in
https://review.opendev.org/c/openstack/ironic/+/786707 using the proposed micro-version 1.74.

This is a follow-on to the bios API support #2165 that should be implemented once the Ironic patch above merges.