The current docs are referring to CONFIG_EFI_BDS - both here in this repo and on the https://github.com/linuxboot/linuxboot.org website.

However, this is no longer to be found; #32 happened, and the original patch (not upstream!) is over at Heads:
https://github.com/linuxboot/heads/blob/master/patches/linux-5.4.69/0000-efi_bds.patch

This is very confusing, and those who don't know are likely having a hard time figuring this out.