update install script

nixos/common/modules/installer.nix

@@ -59,7 +59,7 @@ if [[ $REPLY =~ ^[Yy]$ ]]; then
     --extra-experimental-features "nix-command flakes" \
     --no-write-lock-file \
     -- \
-    --mode zap_create_mount \
+    --mode disko \
     "nixos/hosts/$TARGET_HOST/disks.nix"
 
   sudo nixos-install --no-root-password --flake ".#$TARGET_HOST"

nixos/hosts/nixos-vm-02/disks.nix

@@ -33,6 +33,7 @@
             content = {
               type = "filesystem";
               format = "ext4";
+              mountpoint = "/";
             }; # content.content
           }; # content
         } # partition 2