libvirt: fix tarball hash
libvirt: fix tarball hash

Fixes this failure: https://hydra.nixos.org/build/152776341

Unsure how this happened, but I verified the GPG signatures locally to
make sure the new hash is good.

NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs