rocmPackages.hipblaslt: verify .dat files aren't huge in preInstallCheck

let's avoid regressing compression in future, oops

pkgs/development/rocm-modules/6/hipblaslt/default.nix

@@ -125,7 +125,7 @@ stdenv.mkDerivation (finalAttrs: {
   '';
 
   doCheck = false;
-  doInstallCheck = false;
+  doInstallCheck = true;
 
   nativeBuildInputs = [
     cmake
@@ -213,6 +213,18 @@ stdenv.mkDerivation (finalAttrs: {
       rmdir $out/bin
     '';
 
+  installCheckPhase =
+    # Verify compression worked and .dat files aren't huge
+    ''
+      runHook preInstallCheck
+      find "$out" -type f -name "*.dat" -size "+2M" -exec sh -c '
+          echo "ERROR: oversized .dat file, check for issues with install compression: {}" >&2
+          exit 1
+      ' {} \;
+      echo "Verified .dat files in $out are not huge"
+      runHook postInstallCheck
+    '';
+
   # If this is false there are no kernels in the output lib
   # supporting the target device
   # so if it's an optional dep it's best to not depend on it