tests.cuda.cuda-sample_*: Init at supported CUDA toolkit versions

Since CUDA is unfree, we won't actually use this when testing Nixpkgs
officially. But I want to include this as they are useful for users of
Nixpkgs trying to set up / debug a CUDA environment.

pkgs/test/cuda/default.nix

@@ -0,0 +1,16 @@
+{ callPackage }:
+
+rec {
+  cuda-samplesPackages = callPackage ./cuda-samples { };
+  inherit (cuda-samplesPackages)
+    cuda-samples_cudatoolkit_9
+    cuda-samples_cudatoolkit_9_2
+    cuda-samples_cudatoolkit_10
+    cuda-samples_cudatoolkit_10_0
+    cuda-samples_cudatoolkit_10_1
+    cuda-samples_cudatoolkit_10_2
+    cuda-samples_cudatoolkit_11
+    cuda-samples_cudatoolkit_11_0
+    cuda-samples_cudatoolkit_11_1
+    cuda-samples_cudatoolkit_11_2;
+}