As William points out, the DMTF updated SMBIOS, and the Tianocore project updated EDK2 appropriately.
http://www.basicinputoutput.com/2017/04/small-updates-to-smbios.html
http://www.dmtf.org/standards/smbios
https://github.com/tianocore/edk2/commit/043026ac12c29703bb7e3c19b9ae5e8177bb554b