feat(third_party/nixpkgs): allow setting crossSystem r/6908

This allows cross-compiling depot targets to other architectures, so
`nix-build --argstr crossSystem aarch64-linux -A tvix.nar-bridge`
will emit a cross-compiled aarch64-linux binary.

There's still some other cross-related issues in crate2nix to sort out
for crate2nix builds, but this CL can already land.

Co-Authored-By: raitobezarius <tvl@lahfa.xyz>
Change-Id: I467d49d125dd707a4142bfde18eea4a1c3afaf70
Reviewed-on: https://cl.tvl.fyi/c/depot/+/9755
Reviewed-by: raitobezarius <tvl@lahfa.xyz>
Tested-by: BuildkiteCI

0 files changed, 0 insertions, 0 deletions