zfkerr [1] filed a deletion request for mesa-aco-git [2]: Valve's ACO shader compiler patches for the Mesa Radeon Vulkan driver was merged for Mesa 19.3. So no need anymore for this package.
[1] https://aur.archlinux.org/account/zfkerr/ [2] https://aur.archlinux.org/pkgbase/mesa-aco-git/
