Merge tag 'efi-2021-10-rc1-3' of https://source.denx.de/u-boot/custodians/u-boot-efi

Pull request for efi-2021-10-rc1-3

Documentation:
	provide Makefile documentation

SMBIOS:
	generate BIOS release date based on UEFI version
	improve error handling in SMBIOS table generation

UEFI:
	correct handling of signed capsule if authentication if off