Add a test for ppoll
Add a test for ppoll

nix-rust/nix,Susurrus/nix,xd009642/nix,asomers/nix,MarkusJais/nix-rust,carllerche/nix-rust,nix-rust/nix,MarkusJais/nix-rust,geofft/nix-rust,geofft/nix-rust,Susurrus/nix,Susurrus/nix,carllerche/nix-rust,xd009642/nix,asomers/nix,xd009642/nix,MarkusJais/nix-rust,geofft/nix-rust,carllerche/nix-rust