Merge tag 'rneri-efi-next' of https://github.com/ricardon/efi into next

Pull EFI changes for v3.20 from Ricardo Neri, who kindly picked them up
while I was out on annual leave in December.

Updates included:

 *Rename the function efi_guid_unparse to reflect better its behavior. - Borislav Petkov

 *Update the EFI firmware Kconfig help with the URL of efibootmgr. - Peter Jones

Signed-off-by: Matt Fleming <matt.fleming@intel.com>