flake.nix: remove generating rpi sdImage which is now broken on nixos-22.05

flake.nix

@@ -253,9 +253,6 @@
             inherit (self.nixosConfigurations.${host}) config;
           in
             result //
-            nixpkgs.lib.optionalAttrs (config.system.build ? sdImage) {
-              "${host}-sdImage" = config.system.build.sdImage;
-            } //
             nixpkgs.lib.optionalAttrs (config.system.build ? vm) {
               # boot any machine in a microvm
               "${host}-vm" = (self.nixosConfigurations.${host}
@@ -363,7 +360,6 @@
 
         pulsebert = nixosSystem' {
           modules = [
-            "${inputs.nixpkgs}/nixos/modules/installer/sd-card/sd-image-aarch64.nix"
             ./hosts/pulsebert
           ];
           system = "aarch64-linux";
@@ -373,7 +369,6 @@
           modules = [
             ({ modulesPath, ... }:
             {
-              imports = [ "${modulesPath}/installer/sd-card/sd-image-aarch64.nix" ];
               nixpkgs.overlays = [ heliwatch.overlay ];
               sops.defaultSopsFile = "${secrets}/hosts/radiobert/secrets.yaml";
             })

hosts/radiobert/base.nix

@@ -25,10 +25,13 @@
 
   boot = {
     loader = {
+      grub.enable = false;
       raspberryPi = {
         enable = true;
         version = 4;
-        uboot.enable = true;
+        # TODO: this machine actually has u-boot setup but that's no
+        # longer working with nixos-22.05. DO NOT REBOOT! :-)
+        # uboot.enable = true;
         firmwareConfig = ''
           gpu_mem=192
           dtparam=audio=on
@@ -46,11 +49,6 @@
       # prevent kernel install fail due to missing modules
       pkgs.makeModulesClosure (x // { allowMissing = true; });
   };
-  sdImage = {
-    compressImage = false;
-    imageBaseName = config.networking.hostName;
-    firmwareSize = 512;
-  };
 
   c3d2 = {
     isInHq = false;