This PR adds Hydra-generated bootstrap tarballs for powerpc64le-linux.
I'll be following the script established in PR to tarballs.nixos.org.
Files came from this Hydra build:
https://hydra.nixos.org/build/172142499
Which used nixpkgs revision 49a83445c2
to instantiate:
/nix/store/gj272sd56gsj6qpyzh4njpfzwdhviliz-stdenv-bootstrap-tools-powerpc64le-unknown-linux-gnu.drv
and then built:
/nix/store/n81pljbd8m0xgypm84krc2bnvqgjrfxx-stdenv-bootstrap-tools-powerpc64le-unknown-linux-gnu
I downloaded these files from Hydra with the following commands:
```
STOREPATH=n81pljbd8m0xgypm84krc2bnvqgjrfxx-stdenv-bootstrap-tools-powerpc64le-unknown-linux-gnu
OPTIONS="--option binary-caches https://cache.nixos.org"
nix store add-file \
--name bootstrap-tools.tar.xz \
$(nix-store ${OPTIONS} -r /nix/store/${STOREPATH})/on-server/bootstrap-tools.tar.xz
nix store add-path \
--name busybox \
$(nix-store ${OPTIONS} -r /nix/store/${STOREPATH})/on-server/busybox
```
As @lovesegfault requested in #151399, here are the the `sha256sum`s
of all the `on-server` components for extra verification:
```
$ sha256sum /nix/store/n81pljbd8m0xgypm84krc2bnvqgjrfxx-stdenv-bootstrap-tools-powerpc64le-unknown-linux-gnu/on-server/*
036d062869f7accf0ad89714d12029469dfe6af504f9b226d61eb7d808ad4735 /nix/store/n81pljbd8m0xgypm84krc2bnvqgjrfxx-stdenv-bootstrap-tools-powerpc64le-unknown-linux-gnu/on-server/bootstrap-tools.tar.xz
6bc05832180f5075f4458c32eb0a5e2b673f605884dce01822be474f4e0a63ee /nix/store/n81pljbd8m0xgypm84krc2bnvqgjrfxx-stdenv-bootstrap-tools-powerpc64le-unknown-linux-gnu/on-server/busybox
```
Co-authored-by: Sandro <sandro.jaeckel@gmail.com>