The current description of sys-boot/efibootmgr makes it sound, like it's IA64-only: Interact with the EFI Boot Manager on IA-64 Systems …while it can actually be used on any (U)EFI system. So the last 3 words of the description should be simply dropped to make it: Interact with the EFI Boot Manager
Thanks for the report! + 30 Oct 2013; Mike Gilbert <floppym@gentoo.org> efibootmgr-0.5.4-r1.ebuild, + efibootmgr-0.5.4.ebuild, metadata.xml: + Update DESCRIPTION, bug 489886 by Elias Probst.