qemu: domain: Fix name of macro defining AES IV length
qemu: domain: Fix name of macro defining AES IV length

The initialization vector is a technical term by itself different from
the key.

libvirt/libvirt,VenkatDatta/libvirt,jardasgit/libvirt,fabianfreyer/libvirt,libvirt/libvirt,libvirt/libvirt,fabianfreyer/libvirt,jfehlig/libvirt,olafhering/libvirt,andreabolognani/libvirt,fabianfreyer/libvirt,olafhering/libvirt,olafhering/libvirt,VenkatDatta/libvirt,andreabolognani/libvirt,taget/libvirt,eskultety/libvirt,jfehlig/libvirt,taget/libvirt,taget/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,datto/libvirt,nertpinx/libvirt,zippy2/libvirt,crobinso/libvirt,VenkatDatta/libvirt,datto/libvirt,zippy2/libvirt,eskultety/libvirt,crobinso/libvirt,eskultety/libvirt,olafhering/libvirt,nertpinx/libvirt,andreabolognani/libvirt,datto/libvirt,jfehlig/libvirt,taget/libvirt,taget/libvirt,crobinso/libvirt,crobinso/libvirt,jardasgit/libvirt,datto/libvirt,libvirt/libvirt,eskultety/libvirt,nertpinx/libvirt,andreabolognani/libvirt,VenkatDatta/libvirt,eskultety/libvirt,zippy2/libvirt,zippy2/libvirt,andreabolognani/libvirt,nertpinx/libvirt,VenkatDatta/libvirt,datto/libvirt,nertpinx/libvirt,jardasgit/libvirt,jfehlig/libvirt,jardasgit/libvirt,fabianfreyer/libvirt