Support PUT request to BiosAttributeRegistry

As an internal data provider for the Redfish service, you are certainly free to supply the data in whatever method makes the most sense to you. Many read-only portions of the data model will need to be supplied by some internal firmware components, like filling in CPU and memory information populated by UEFI. The scope of what's published in the Redfish Specification and Redfish Schema Bundle is focused on the end-user experience. An end-user of Redfish will never be able to perform these operations, hence why the capabilities in the schema contain "false".