prmers: add update-script (#472773)

Author: edwtjo

pkgs/by-name/pr/prmers/package.nix

@@ -7,6 +7,7 @@
   opencl-headers,
   stdenv,
   versionCheckHook,
+  nix-update-script,
 }:
 
 stdenv.mkDerivation (finalAttrs: {
@@ -44,6 +45,8 @@ stdenv.mkDerivation (finalAttrs: {
 
   versionCheckProgramArg = "-v";
 
+  passthru.updateScript = nix-update-script { extraArgs = [ "--version=unstable" ]; };
+
   meta = {
     description = "GPU-accelerated Mersenne primality testing";
     longDescription = ''