all systems: enable memtest86; blue/nix_store: set read only

mediabox/configuration.nix

@@ -37,8 +37,11 @@
     kernelModules = ["acpi_call"];
     kernelPackages = pkgs.linuxPackages_latest;
     kernelParams = ["msr.allow_writes=on"];
-    loader.systemd-boot.editor = false;
-    loader.systemd-boot.enable = true;
+    loader.systemd-boot = {
+      editor = false;
+      enable = true;
+      memtest86.enable = true;
+    };
     readOnlyNixStore = true;
     supportedFilesystems = ["btrfs"];
     tmpOnTmpfs = true;
@@ -142,7 +145,7 @@
         wantedBy = ["default.target" "suspend.target" "shutdown.target"];
       };
 
-      /* 
+      /*
       "cpu_setting" = {
         description = "Enable turboot boost and undervolt cpu after suspend";
         wantedBy = ["post-resume.target" "multi-user.target"];