Move CPU optimizations into their own role.

This is remove duplication between the individual hosts folders.

nix/configuration/hosts/ionlybootzfs/default.nix

@@ -24,7 +24,6 @@
   imports = [
     ./wrapped-disk-config.nix
     ./hardware-configuration.nix
-    ./optimized_build.nix
   ];
 
   # Generate with `head -c4 /dev/urandom | od -A none -t x4`
@@ -35,9 +34,24 @@
   time.timeZone = "America/New_York";
   i18n.defaultLocale = "en_US.UTF-8";
 
-  me.optimizations.enable = false;
   me.secureBoot.enable = true;
 
+  me.optimizations = {
+    enable = false;
+    arch = "znver4";
+    system_features = [
+      "gccarch-znver4"
+      "gccarch-skylake"
+      # "gccarch-alderlake" missing WAITPKG
+      "gccarch-x86-64-v3"
+      "gccarch-x86-64-v4"
+      "benchmark"
+      "big-parallel"
+      "kvm"
+      "nixos-test"
+    ];
+  };
+
   # Mount tmpfs at /tmp
   boot.tmp.useTmpfs = true;