scrypt: fix build of pkgsStatic.scrypt
scrypt: fix build of pkgsStatic.scrypt

The getconf input defaults to the glibc one if it is being used and uses
the netbsd version in all other cases. This fixes the build when
building with musl, since it doesn't ship a version of getconf.

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